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NCERT Solutions for CBSE Class 7 Mathematics Chapter 10: Ratios, Proportions and Percentages

Welcome to the complete NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages. This chapter equips you with three interconnected tools that power everyday decisions: ratios for comparison, proportions for scaling, and percentages for universal representation. From calculating how much sugar you need if a recipe doubles, to figuring out the discount on your favorite book, to understanding the interest your parents earn on savings — Ratios, Proportions and Percentages form the arithmetic backbone of commerce, science and daily life. In the following sections, you will find detailed solutions to every NCERT exercise, explanations of key formulae, worked examples mirroring board exam patterns, and FAQs that address common doubts. Let us dive straight into mastering CBSE Class 7 Mathematics Chapter 10.

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Key takeaways

  • ✓A ratio compares two quantities of the same kind; always simplify by dividing both terms by their Highest Common Factor to reach simplest form.
  • ✓In a proportion a: b = c: d, the cross-multiplication rule a × d = b × c lets you solve for any unknown term efficiently.
  • ✓Percentage means 'per hundred' — convert to fraction (divide by 100), multiply to find percentage of a number, and express parts universally.
  • ✓Profit % and Loss % are always calculated on Cost Price, never on Selling Price: Profit % = (Profit ÷ CP) × 100.
  • ✓Simple Interest depends on Principal, Rate and Time: SI = (P × R × T) ÷ 100; Amount = Principal + SI.
  • ✓Direct proportion means both quantities increase together in the same ratio (e.g. cost and quantity); set up equal ratios and cross-multiply.
  • ✓Real-life applications of CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages include discounts, taxes, bank interest, recipe scaling and comparing speeds.

Understanding Ratios — Comparing Quantities the NCERT Way

A ratio is a method of comparing two quantities of the same kind, expressed in the form a: b. The NCERT textbook for CBSE Class 7 Mathematics Chapter 10 defines ratio as the relationship between two numbers, showing how many times one value contains or is contained within the other. For instance, if a classroom has 20 boys and 15 girls, the ratio of boys to girls is 20: 15. However, ratios must be presented in their simplest form by dividing both terms by their Highest Common Factor (HCF). Here, HCF of 20 and 15 is 5, so the simplest ratio is 4: 3. A simplified ratio makes comparison clearer and is the standard expected in CBSE exams. Ratios can also be viewed as fractions: the ratio 4: 3 means boys form 4/7 of the class and girls 3/7, since total parts = 4 + 3 = 7. Important: both quantities must have the same unit before forming a ratio (e.g. both in kilograms or both in rupees). Ratios appear everywhere — ingredient proportions in recipes, mixing paint colors, gear ratios in bicycles, and student-teacher ratios in schools. Mastering simplification and interpretation of ratios is the first pillar of CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages.
  • A ratio a: b compares two quantities; read as 'a to b'.
  • Simplify by dividing both terms by their HCF until HCF becomes 1.
  • Ratios can be written as fractions: 3: 2 is the same as 3/2 when comparing the first quantity to the second.
  • Both quantities must be in the same unit (convert if necessary before forming the ratio).
  • Example: Ratio of 50 cm to 2 m → Convert 2 m = 200 cm → Ratio = 50: 200 = 1: 4.

Step-by-Step Method to Simplify Ratios

Simplifying ratios is a core skill tested repeatedly in CBSE Class 7 Mathematics Chapter 10 exercises. The process mirrors fraction simplification. Step 1: Identify the two terms of the ratio. Step 2: Find the HCF (Highest Common Factor) of both terms using prime factorization or the division method. Step 3: Divide both terms by the HCF. Step 4: Write the resulting ratio; verify that the HCF of the new terms is 1. Let's walk through an example from the NCERT textbook pattern. Suppose you need to simplify the ratio 36: 48. Find HCF: Prime factors of 36 = 2 × 2 × 3 × 3; Prime factors of 48 = 2 × 2 × 2 × 2 × 3. Common factors = 2 × 2 × 3 = 12. So HCF = 12. Now divide: 36 ÷ 12 = 3 and 48 ÷ 12 = 4. Simplified ratio = 3: 4. Check: HCF of 3 and 4 is 1, so this is fully simplified. Another example: Simplify 125: 200. HCF = 25. Divide: 125 ÷ 25 = 5, 200 ÷ 25 = 8. Answer: 5: 8. This skill is foundational because NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 expect you to present all final ratios in simplest form unless otherwise stated.

Proportions and the Cross-Multiplication Rule

A proportion states that two ratios are equal. If a: b = c: d, we say these four quantities are in proportion. The NCERT framework for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages emphasizes the cross-multiplication property: in any proportion a: b = c: d, the product of the extremes equals the product of the means, i.e., a × d = b × c. Here, a and d are the extremes (outer terms) and b and c are the means (inner terms). This property is your main tool for solving proportion problems. Suppose 5 pens cost Rs 75; you want to find the cost of 8 pens. Set up the proportion: 5: 75 = 8: x (where x is the unknown cost). Cross-multiply: 5 × x = 75 × 8, so 5x = 600, thus x = 120. Therefore 8 pens cost Rs 120. This is called direct proportion because as the number of pens increases, the cost increases in the same ratio. Proportions underpin real-world scaling: if 3 workers complete a task in 12 days, proportions help you find how many days 9 workers need (inverse proportion, studied later). Every NCERT exercise in CBSE Class 7 Mathematics Chapter 10 on proportions tests your ability to set up the correct ratio equation and apply cross-multiplication accurately.
  • Proportion: Two equal ratios, written a: b = c: d or a/b = c/d.
  • Cross-multiplication rule: a × d = b × c. Use this to solve for an unknown.
  • If three terms are known, the fourth can always be calculated.
  • Direct proportion: both quantities increase or decrease together (cost vs quantity, distance vs time at constant speed).
  • Inverse proportion (advanced): one increases as the other decreases (workers vs days for a fixed task); covered later in Class 8.

Percentage — The Universal Language of Comparison

Percentage literally means 'per hundred' and is denoted by the symbol %. When you say 25%, you mean 25 out of every 100, or the fraction 25/100, which simplifies to 1/4. Percentages allow comparison across different totals. For instance, if School A has 40 out of 200 students pass an exam and School B has 30 out of 150 students pass, comparing 40 vs 30 is misleading. Convert to percentages: School A = (40/200) × 100 = 20%; School B = (30/150) × 100 = 20%. Both schools have the same pass rate! The NCERT textbook for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages teaches four key conversions. (1) Percentage to Decimal: Divide by 100 (e.g., 35% = 0.35). (2) Decimal to Percentage: Multiply by 100 (e.g., 0.8 = 80%). (3) Percentage to Fraction: Write as fraction over 100 and simplify (e.g., 60% = 60/100 = 3/5). (4) Fraction to Percentage: Multiply fraction by 100 (e.g., 7/20 = (7/20) × 100 = 35%). To find a percentage of a number, use the formula: (Percentage/100) × Number. Example: Find 15% of 240. Answer: (15/100) × 240 = 0.15 × 240 = 36. Percentage problems dominate Class 7 Mathematics Chapter 10 exercises and appear in every CBSE board exam.

Calculating Percentage of a Quantity — Worked Examples

One of the most practical skills from CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages is computing what percentage one quantity is of another, or finding a given percentage of a number. The NCERT textbook provides the standard formula: To find what % A is of B, use (A/B) × 100. To find X% of a number N, use (X/100) × N. Let us work through examples. Example 1: In a class of 50 students, 12 are absent. What percentage are absent? Solution: (12/50) × 100 = 0.24 × 100 = 24%. So 24% of students are absent. Example 2: A shopkeeper gives a 15% discount on a shirt priced at Rs 600. What is the discount amount and the final price? Solution: Discount = 15% of 600 = (15/100) × 600 = 0.15 × 600 = Rs 90. Final price = 600 − 90 = Rs 510. Example 3: 35% of a number is 140. Find the number. Solution: Let the number be x. Then (35/100) × x = 140, so 0.35x = 140, thus x = 140 ÷ 0.35 = 400. The number is 400. These problem types recur in every NCERT exercise and school exam for Class 7 Mathematics Chapter 10.

Profit and Loss — Definitions and Core Formulae

Profit and Loss problems are central to CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages and mirror real-life business transactions. When a trader buys goods at one price and sells at another, the difference determines profit or loss. Cost Price (CP) is the price at which an item is purchased. Selling Price (SP) is the price at which it is sold. If SP > CP, the trader makes a Profit = SP − CP. If SP < CP, the trader incurs a Loss = CP − SP. To compare profit or loss across different transactions, we express them as percentages of the Cost Price. Profit Percentage = (Profit / CP) × 100. Loss Percentage = (Loss / CP) × 100. Crucially, the denominator is always CP, not SP. This is a common error trap in exams. Example: A fruit vendor buys mangoes at Rs 30 per kg and sells at Rs 36 per kg. CP = Rs 30, SP = Rs 36. Profit = 36 − 30 = Rs 6 per kg. Profit % = (6 / 30) × 100 = 20%. Conversely, if he sells at Rs 27 per kg: Loss = 30 − 27 = Rs 3. Loss % = (3 / 30) × 100 = 10%. The NCERT textbook drills these formulae through multiple word problems, testing your ability to identify CP, SP, and apply the correct formula.
  • Cost Price (CP): Price at which goods are bought.
  • Selling Price (SP): Price at which goods are sold.
  • Profit = SP − CP (when SP > CP); Loss = CP − SP (when CP > SP).
  • Profit % = (Profit ÷ CP) × 100; Loss % = (Loss ÷ CP) × 100.
  • Always base percentage on Cost Price, not Selling Price.
  • If CP and profit % are given, find SP using: SP = CP + (Profit% / 100) × CP.
  • If CP and loss % are given, find SP using: SP = CP − (Loss% / 100) × CP.

Solving Profit and Loss Problems — NCERT Exercise Patterns

NCERT exercises in CBSE Class 7 Mathematics Chapter 10 present profit and loss in varied formats: direct calculation, reverse calculation (finding CP when SP and profit% are known), and combined scenarios. Let us solve representative problems. Problem 1: A shopkeeper buys a bicycle for Rs 1200 and sells it for Rs 1350. Find profit and profit %. Solution: CP = 1200, SP = 1350. Profit = 1350 − 1200 = 150. Profit % = (150 / 1200) × 100 = 12.5%. Problem 2: A woman buys a watch for Rs 800 and sells it at a loss of 5%. Find the selling price. Solution: Loss % = 5, so Loss = (5/100) × 800 = Rs 40. SP = CP − Loss = 800 − 40 = Rs 760. Problem 3 (reverse): A book is sold for Rs 240 at a profit of 20%. Find its cost price. Solution: Let CP = x. Profit = 20% of x = 0.2x. SP = CP + Profit, so 240 = x + 0.2x = 1.2x. Thus x = 240 / 1.2 = Rs 200. The cost price is Rs 200. These problem structures are repeated across NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages, ensuring mastery through practice.

Simple Interest — Formula, Components and Applications

Simple Interest (SI) is the extra money paid or earned on a loan or deposit, calculated only on the original sum (Principal), not on accumulated interest. The NCERT textbook for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages introduces SI with the formula: SI = (P × R × T) / 100, where P = Principal (the original sum in rupees), R = Rate of interest (percentage per annum), and T = Time (in years). The total Amount to be repaid or received is A = P + SI. Example: You deposit Rs 4000 in a bank at 5% per annum for 3 years. P = 4000, R = 5, T = 3. SI = (4000 × 5 × 3) / 100 = 60000 / 100 = Rs 600. Amount = 4000 + 600 = Rs 4600. So after 3 years, your Rs 4000 grows to Rs 4600. Simple Interest problems appear in bank deposits, loans, and borrowing scenarios. Key point: Time must be in years; if given in months, convert (e.g., 6 months = 0.5 years). If given in days, use T = (number of days / 365). CBSE exams test all three variables: finding SI when P, R, T are given; finding P when SI, R, T are known; and finding R or T given the other parameters. Mastery of the SI formula and its rearrangements is essential for scoring full marks in Class 7 Mathematics Chapter 10.
  • Simple Interest (SI) = (P × R × T) / 100
  • Principal (P): Original sum borrowed or invested (in rupees)
  • Rate (R): Interest rate per annum (as a percentage, e.g., 8 means 8%)
  • Time (T): Duration in years (convert months or days to years if necessary)
  • Amount (A) = Principal + SI = P + (P × R × T)/100
  • If time is 6 months, T = 6/12 = 0.5 years; if 180 days, T = 180/365 years
  • To find Principal when SI, R, T are known: P = (SI × 100) / (R × T)
  • To find Rate: R = (SI × 100) / (P × T); To find Time: T = (SI × 100) / (P × R)

Simple Interest Worked Examples — NCERT Pattern

The NCERT exercises for CBSE Class 7 Mathematics Chapter 10 include direct SI calculation, reverse problems (finding P, R or T), and real-world applications combining profit/loss with SI. Example 1: Find the simple interest on Rs 2500 at 6% per annum for 4 years. Also find the amount. Solution: P = 2500, R = 6, T = 4. SI = (2500 × 6 × 4) / 100 = 60000 / 100 = Rs 600. Amount = 2500 + 600 = Rs 3100. Example 2: At what rate percent per annum will Rs 5000 amount to Rs 5600 in 3 years under simple interest? Solution: Amount = 5600, P = 5000, so SI = 5600 − 5000 = Rs 600. T = 3 years. Using SI = (P × R × T)/100, we have 600 = (5000 × R × 3)/100. Simplify: 600 = 150R. R = 600 / 150 = 4. Rate = 4% per annum. Example 3: A sum of money doubles itself in 10 years at simple interest. Find the rate of interest. Solution: Let Principal = P. Amount = 2P. So SI = 2P − P = P. T = 10 years. P = (P × R × 10)/100. Cancel P: 1 = R × 10 / 100. So R = 100 / 10 = 10%. Rate = 10% per annum. These examples mirror the variety in NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages.

Real-World Applications — Shopping, Banking and Everyday Math

CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages is uniquely practical. Ratios appear in recipes (if a recipe for 4 people uses 2 cups of rice, how much for 10 people? Set up proportion 4: 2 = 10: x, solve x = 5 cups). Percentages dominate shopping: a 30% discount on a Rs 1500 jacket saves you Rs 450. Profit and loss help you evaluate if a business is viable: if production cost is Rs 50 and selling price is Rs 70, the 40% profit margin indicates healthy returns. Simple interest is the foundation of savings accounts, fixed deposits and small loans. Suppose your parents invest Rs 50,000 in a fixed deposit at 7% per annum for 2 years; SI = (50000 × 7 × 2)/100 = Rs 7000, so maturity amount = Rs 57,000. Even tax calculations, inflation rates, population growth rates and election vote-share analysis use percentages. The NCERT framework emphasizes these contexts to show that mathematics is not abstract — every concept in Class 7 Mathematics Chapter 10 has a daily application. By mastering ratios, proportions and percentages, you become a more informed consumer, saver and citizen. This chapter directly prepares you for higher classes (compound interest in Class 8, algebra-based profit/loss in Class 9) and real-life decision-making.
  • Recipe scaling: Use proportions to adjust ingredient quantities for different servings.
  • Discounts and sales: Calculate actual savings and final price using percentage formulas.
  • Profit margins: Businesses use profit % to decide pricing strategies and measure profitability.
  • Bank savings: Simple interest helps compare fixed deposit schemes and savings account returns.
  • Taxes: GST, income tax, and service charges are computed as percentages of base amounts.
  • Comparing data: Percentages let you compare election results, exam pass rates, or survey responses across different sample sizes.
  • Speed and distance: Ratios and proportions solve 'if a car covers 180 km in 3 hours, how far in 5 hours?' type problems.

Common Mistakes and How to Avoid Them — Expert Tips

Students often lose marks in CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages due to avoidable errors. Mistake 1: Not simplifying ratios. If an answer is 20: 30, always simplify to 2: 3. Examiners deduct marks for unsimplified ratios. Mistake 2: Calculating profit/loss % on Selling Price instead of Cost Price. Remember: the denominator is always CP. If CP = 200 and profit = 50, profit % = (50/200) × 100 = 25%, not (50/250) × 100. Mistake 3: Writing 25% as 25 in calculations instead of 25/100 or 0.25. Always convert percentage to decimal or fraction before arithmetic. Mistake 4: In proportions, swapping terms incorrectly. If 5 books cost Rs 100, for 8 books set 5: 100 = 8: x, not 5: 8 = 100: x. Mistake 5: Forgetting to convert time to years in SI problems. If time is given as 18 months, convert to 18/12 = 1.5 years before substituting in the formula. Mistake 6: Mixing up profit and profit %. Profit is in rupees; profit % is a ratio. State units clearly. Mistake 7: Rounding prematurely in multi-step problems; carry full precision until the final answer. Pro tip: After solving, re-read the question to ensure you answered what was asked (e.g., 'find the profit %' not just 'find profit'). These pitfalls are well-documented in NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 and avoiding them can boost your score significantly.
  • Always simplify ratios to simplest form by dividing by HCF.
  • Base profit % and loss % on Cost Price, never Selling Price.
  • Convert percentages to fractions or decimals before multiplying (e.g., 15% = 0.15).
  • Set up proportions carefully: keep corresponding quantities in matching positions.
  • Convert time to years in SI problems (months to years: divide by 12; days to years: divide by 365).
  • State whether your answer is a rupee amount or a percentage — add units.
  • Do not round intermediate steps; round only the final answer to required decimal places.
  • Re-check what the question asks: 'find CP' vs 'find profit' vs 'find profit %' are different.

Connecting to CBSE Exam Pattern and Marking Scheme

In the CBSE Class 7 Mathematics annual examination, Chapter 10 Ratios, Proportions and Percentages typically carries 10–15 marks out of 80 (internal assessments add 20 marks, making the total 100). Questions range from 1-mark MCQs (e.g., 'Simplify the ratio 45: 60') to 2-mark short-answer problems ('Find 18% of 250') to 3- or 4-mark long-answer word problems combining profit, loss and SI ('A shopkeeper buys 50 kg rice at Rs 40/kg, sells 30 kg at Rs 50/kg and remaining at Rs 45/kg; find overall profit %'). The 2024-25 CBSE syllabus retains the NCERT textbook as the sole prescribed material, so every exercise in the NCERT book is exam-relevant. Internal assessments (periodic tests, notebook, subject enrichment) evaluate your ability to present step-by-step solutions, use correct formulae, and apply concepts to real scenarios (project on 'compare simple interest across three banks'). Board examiners award partial marks for correct method even if the final numerical answer is wrong, so always show your working: write the formula, substitute values, and solve step-by-step. High-scoring students practice all NCERT exercise problems, especially word problems, and cross-verify answers using CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages NCERT Solutions. Mastery of this chapter also strengthens your foundation for Class 8 (compound interest, inverse proportion) and Class 9 (algebraic profit/loss, advanced percentage applications).

How CBSETUTOR.ai Supports Mastery of Chapter 10

CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages contains over 50 exercise problems across multiple sections, and students often need step-by-step guidance beyond the textbook. CBSETUTOR.ai is India's 24×7 AI tutor designed for CBSE Classes 6–12, having ingested every NCERT textbook page, CBSE sample paper and marking scheme. When your child is stuck on a proportion word problem at 9 pm — long after tuition hours — they can simply photograph the problem and upload it to CBSETUOR.ai. Within seconds, the AI provides a worked solution aligned with NCERT terminology, highlights the exact formula, and explains each step in simple language. Unlike generic tools, CBSETUTOR.ai knows that profit % must use CP as denominator, recognizes NCERT question patterns, and offers hints before full solutions (building problem-solving skills, not just answer-copying). For Class 7 Mathematics Chapter 10, the platform offers topic-wise practice (pure ratio problems, pure percentage problems, profit/loss, SI), instant doubt resolution, and exam-style mock questions. Parents across Delhi, Mumbai, Bengaluru and Tier-2 cities use CBSETUTOR.ai because it is faster than WhatsApp groups, more reliable than YouTube (which often teaches non-NCERT methods), and costs just ₹999/month for full access to Classes 6–12 — less than two hours of private tuition. Three-day free trial, no credit card required. When your child masters every NCERT exercise in CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages with CBSETUTOR.ai, they walk into exams with confidence and clarity.

Frequently asked questions

Why must ratios always be simplified to their simplest form in CBSE Class 7 Mathematics Chapter 10?+
Ratios in simplest form make comparison clearer and are the standard expected by CBSE examiners. An unsimplified ratio like 20: 30 can lose you marks even if mathematically equivalent to 2: 3. Simplification by dividing both terms by their HCF ensures the ratio is in its most reduced, universally comparable form.
How do I know when to set up a direct proportion versus an inverse proportion in word problems?+
In direct proportion, both quantities increase or decrease together (e.g., more items cost more money, more distance takes more time at constant speed). In inverse proportion, one increases as the other decreases (e.g., more workers complete a task in fewer days). CBSE Class 7 Mathematics Chapter 10 focuses on direct proportion; inverse proportion is introduced in Class 8. Look for clues: if doubling one quantity doubles the other, it is direct.
Why is profit percentage always calculated on Cost Price and not Selling Price?+
Profit % on Cost Price is the business standard because CP is the investment base. Calculating on SP would give inconsistent comparisons across transactions. NCERT strictly defines Profit % = (Profit ÷ CP) × 100. Using SP as denominator is a common mistake that examiners penalize heavily in CBSE Class 7 Mathematics Chapter 10 exams.
If a question says 'time is 18 months', do I use T = 18 in the Simple Interest formula?+
No. The SI formula SI = (P × R × T)/100 requires Time in years. Convert 18 months to years: 18 ÷ 12 = 1.5 years. So use T = 1.5. If time is given in days, divide by 365. This conversion is a frequent error point in CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages exams.
Can I write 25% directly as 25 when calculating percentage of a number?+
No. You must convert 25% to a fraction (25/100) or decimal (0.25) before multiplying. Writing 25% of 200 as 25 × 200 = 5000 is wrong. Correct: (25/100) × 200 = 0.25 × 200 = 50. This is a basic error that costs marks in every CBSE Class 7 Mathematics Chapter 10 test.
How can I check if my proportion setup is correct before solving?+
Write the two ratios with units and verify corresponding quantities are in matching positions. For example, if 5 kg rice costs Rs 100, for 8 kg: set 5 kg: 100 Rs = 8 kg: x Rs. Check: left side has kg on top and Rs on bottom; right side must match. Cross-multiply only after confirming the setup. This discipline prevents errors in CBSE Class 7 Mathematics Chapter 10 proportion problems.
What is the difference between profit (in rupees) and profit percentage?+
Profit in rupees is the absolute difference: SP − CP. Profit percentage is that difference expressed as a percentage of CP: (Profit ÷ CP) × 100. Exam questions often ask for profit %, so even if you calculate profit correctly, you must take the extra step of dividing by CP and multiplying by 100. CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages exercises test both.
If Selling Price and profit % are given, how do I find Cost Price?+
Let CP = x. Profit = (profit % / 100) × x. Then SP = CP + Profit = x + (profit % / 100) × x = x × (1 + profit %/100). Rearrange: x = SP / (1 + profit %/100). For example, SP = Rs 450, profit % = 12.5. Then CP = 450 / (1 + 0.125) = 450 / 1.125 = Rs 400. This reverse calculation is common in NCERT Class 7 Mathematics Chapter 10 exercises.
Does CBSE allow calculators in Class 7 Mathematics exams for Chapter 10 problems?+
No. CBSE Class 7 annual exams do not permit calculators. All arithmetic (simplification, percentage calculations, SI) must be done manually. Practice mental math and standard algorithms (long division, multiplication) to build speed and accuracy for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages.
How is Simple Interest different from Compound Interest, and will we study CI in Class 7?+
Simple Interest is calculated only on the Principal for the entire duration. Compound Interest calculates interest on Principal plus accumulated interest each period, so interest compounds. CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages covers only Simple Interest. Compound Interest is introduced in Class 8 Chapter 8.
My child's school uses a different textbook. Are these NCERT Solutions still useful?+
Yes. CBSE prescribes NCERT as the official textbook for Classes 6–12, and board exams are set strictly from NCERT content. Even if your school uses a supplementary book (RS Aggarwal, RD Sharma), NCERT exercises remain the foundation. Mastering NCERT Solutions for CBSE Class 7 Mathematics Chapter 10 Ratios, Proportions and Percentages ensures your child meets the board standard.
How can CBSETUTOR.ai help if my child struggles with word problems in this chapter?+
CBSETUTOR.ai is an AI tutor trained on every NCERT textbook for Classes 6–12. Your child can upload a photo of any word problem from CBSE Class 7 Mathematics Chapter 10, and the AI will break it into steps: identify given data, choose the correct formula (ratio, proportion, profit/loss, SI), substitute and solve, and explain the reasoning. Available 24×7 at ₹999/month (one price for all classes 6–12), with a 3-day free trial and no card required. It is like having a patient tutor on call anytime your child needs help.

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