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Fractions in Disguise

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Page 2: Can you tell what percentage of the colour was made using yellow?
Page 3: Try completing Method 3 by filling the boxes.
Page 3: Express the following fractions as percentages. (i) 3/5 (ii) 7/14 (iii) 9/20 (iv) 72/150 (v) 1/3 (vi) 5/11
Page 3: Nandini has 25 marbles, of which 15 are white. What percentage of her marbles are white? (i) 10% (ii) 15% (iii) 25%…
Page 4: In a school, 15 of the 80 students come to school by walking. What percentage of the students come by walking?
Page 4: A group of friends is participating in a long-distance run. The positions of each of them after 15 minutes are shown…
Page 4: Pairs of quantities are shown below. Identify and write appropriate symbols ‘>’, ‘ (i) 50% ___ 5% (ii) 5/10 ___ 50%…
Page 5: • The human body, on average, is about 60% water by weight. • Ice cream is about 30–50% air by volume. • 45% of the…
Page 6: Suppose Madhu ate 120 g of biscuits and Madhav ate 95 g of biscuits. Who consumed more sugar? Try to find out.
Page 7: Try to calculate (without using pen and paper) the indicated percentages of the values shown in the table below.…
Page 7: You may have noticed that 20% of a value is double that of 10% of the same value. This will always happen, since 20%…
Page 8: Using this observation, mentally calculate how much 15% of the values in the table would be. Suppose you have to…
Page 8: Similarly, to find 10% of a quantity, what decimal value should be multiplied?
Page 8: Complete the following table:
Page 8: Make a pair. Each of you choose a number. Suppose, the numbers chosen are a and b. Share your numbers with each…
Page 9: Estimate first what percentage 2/9 would be.
Page 10: Estimate first before solving further.
Page 11: In the next two days, he made ₹5000 and ₹6000 respectively. What percentage of his target are these values? What…
Page 11: On Days 5 and 6 his sales were ₹7800 and ₹9550 respectively. Calculate the percentage of the target achieved on…
Page 12: On Day 7, he achieved 150% of his target. On Day 8, he achieved 210% of his target. Find the sales made on these days.
Page 12: Complete the table below. Mark the approximate locations in the following diagram.
Page 12: Find the missing numbers. The first problem has been worked out. (ii) A bar of 9 equal cells = 100%. What percentage…
Page 13: Find the value of the following and also draw their bar models. (i) 25% of 160 (ii) 16% of 250 (iii) 62% of 360 (iv)…
Page 13: Surya made 60 ml of deep orange paint, how much red paint did he use if red paint made up 3/4 of the deep orange paint?
Page 13: Pairs of quantities are shown below. Identify and write appropriate symbols ‘>’, ‘ (i) 50% of 510 ⬜ 50% of 515 (ii)…
Page 13: Fill in the blanks appropriately: (i) 30% of k is 70, 60% of k is ____, 90% of k is ____, 120% of k is ______. (ii)…
Page 13: Fill in the blanks: (i) 3 is ____ % of 300. (ii) _____ is 40% of 4. (iii) 40 is 80% of _____.
Page 13: Is 10% of a day longer than 1% of a week? Create such questions and challenge your peers.
Page 13: Represent these quantities as percentages. This task can be distributed among the class. What do you observe?
Page 14: Workers in a coffee plantation take 18 days to pick coffee berries in 20% of the plantation. How many days will they…
Page 14: The badminton coach has planned the training sessions such that the ratio of warm up : play : cool down is 10% : 80%…
Page 14: An estimated 90% of the world’s population lives in the Northern Hemisphere. Find the (approximate) number of people…
Page 14: A recipe for the dish, halwa, for 4 people has the following ingredients in the given proportions — Rava: 40%,…
Page 15: Complete this table by calculating the percentages to answer the questions: Check if the percentages of each product…
Page 16: Example 3: Do the following two statements mean the same thing? (i) The population of this state in 1991 is 165% of…
Page 17: Example 4: Find out the percentage profit Kishanlal made on this sweater.
Page 17: Find the profit percentage of the wholesaler and the manufacturer.
Page 17: Shambhavi owns a stationery shop. She procures 200 page notebooks at ₹36 per book. She sells them with a profit…
Page 17: She sells crayon boxes at ₹50 per box with a profit margin of 25%. How much did Shambhavi buy them from the wholesaler?
Page 17: Could we have just calculated the loss percentage per kg instead? Would it be the same?
Page 18: Try making an estimate. Draw a rough diagram depicting the given situation.
Page 18: Due to heavy rains, Snehal could not transport strawberries to Hyderabad from his farm in Panchgani. He sells some…
Page 18: A utensil store is offering a 35% discount on the cooker with an MRP ₹1800. What is the selling price? If the cost…
Page 18: Why are there two different, equally correct "profit percentages" here — 50% and 33.33% — for the very same ₹250…
Page 19: Check if the calculations are correct in the bill shown.
Page 19: If a shopkeeper buys a geometry box for ₹75 and sells it for ₹110, what is his profit margin with respect to the cost?
Page 19: I am a carpenter and I make chairs. The cost of materials for a chair is ₹475 and I want to have a profit margin of…
Page 19: The total sales of a company (also called revenue) was ₹2.5 crore last year. They had a healthy profit margin of…
Page 19: A clothing shop offers a 25% discount on all shirts. If the original price of a shirt is ₹300, how much will Anwar…
Page 19: The petrol price in 2015 was ₹60 and ₹100 in 2025. What is the percentage increase in the price of petrol? (i) 50%…
Page 20: Samson bought a car for ₹4,40,000 after getting a 15% discount from the car dealer. What was the original price of…
Page 20: 1600 people voted in an election and the winner got 500 votes. What percent of the total votes did the winner get?…
Page 20: The price of 1 kg of rice was ₹38 in 2024. It is ₹42 in 2025. What is the rate of inflation? (Inflation is the…
Page 20: A number increased by 20% becomes 90. What is the number?
Page 20: A milkman sold two buffaloes for ₹80,000 each. On one of them, he made a profit of 5% and on the other a loss of…
Page 20: The population of elephants in a national park increased by 5% in the last decade. If the population of the…
Page 20: Which of the following statement(s) mean the same as — "The demand for cameras has fallen by 85% in the last…
Page 21: Example 7: If one deposits ₹6000 in the bank, what is the amount after 3 years? There are two possibilities: Option…
Page 22: Bank of Yahapur offers an interest of 10% p.a. Compare how much one gets if they deposit ₹20,000 for a period of 2…
Page 23: Bank of Wahapur offers an interest of 5% p.a. Compare how much one gets if one deposits ₹20,000 for a period of 4…
Page 23: Let us try to generalise the pattern observed in each of the options, using p (principal), r (rate as a fraction)…
Page 24: Suppose we want to know the expression/formula to find the total interest amount gained at the end of the maturity…
Page 24: Jasmine invests amount 'p' for 4 years at an interest of 6% p.a. Which of the following expression(s) describe the…
Page 24: The post office offers an interest of 7% p.a. How much interest would one get if one invests ₹50,000 for 3 years…
Page 24: Giridhar borrows a loan of ₹12,500 at 12% per annum for 3 years without compounding, and Raghava borrows the same…
Page 24: Consider an amount ₹1000. If it grows at 10% p.a., how long will it take to double when compounding is done vs. when…
Page 24: The population of a city is rising by about 3% every year. If the current population is 1.5 crore, what is the…
Page 24: In a laboratory, the number of bacteria in a certain experiment increases at the rate of 2.5% per hour. Find the…
Page 25: Example 10: A TV is bought at a price of ₹21,000. After 1 year, the value of the TV depreciates by 5%. Find the…
Page 25: Example 11: The population of a village was observed to be reducing by about 10% every decade. If the current…
Page 25: You have won a contest. The organisers offer you two options to choose from: Option A: You deposit ₹100 and you get…
Page 26: A provision store is offering a stock clearance sale. Customers can choose one of the two options — 20% discount or…
Page 26: Example 12: A bakery called Cakely is offering a 30% + 20% discount on all cakes. Another bakery called Cakify is…
Page 27: (i) Do you think she didn’t make any loss? (ii) If she had sold goods (originally) for ₹12,000 after discount, how…
Page 27: Ariba and Arun have some marbles. Ariba says, "The number of marbles with me is 120% of the marbles Arun has." What…
Page 28: The population of Bengaluru in 2025 is about 250% of its population in 2000. If the population in 2000 was 50 lakhs,…
Page 28: The population of the world in 2025 is about 8.2 billion. The populations of some countries in 2025 are given. Match…
Page 28: The price of a mobile phone is ₹8250. A GST of 18% is added to the price. Which of the following gives the final…
Page 28: The monthly percentage change in population (compared to the previous month) of mice in a lab is given: Month 1…
Page 28: A shopkeeper initially set the price of a product with a 35% profit margin. Due to poor sales, he decided to offer a…
Page 28: What percentage of area is occupied by the region marked ‘E’ in the figure?
Page 29: What is 5% of 40? What is 40% of 5? What is 25% of 12? What is 12% of 25? What is 15% of 60? What is 60% of 15? What…
Page 29: A school is organising an excursion for its students. 40% of them are Grade 8 students and the rest are Grade 9…
Page 29: A shopkeeper sells pencils at a price such that the selling price of 3 pencils is equal to the cost price of 5…
Page 29: The bus fares were increased by 3% last year and by 4% this year. What is the overall percentage price increase in…
Page 29: If the length of a rectangle is increased by 10% and the area is unchanged, by what percentage (exactly) does the…
Page 29: Find out the weight each ingredient makes up in this packet.
Page 29: Three shops sell the same items at the same price. The shops offer deals as follows: Shop A: "Buy 1 and get 1 free".…
Page 30: In a room of 100 people, 99% are left-handed. How many left-handed people have to leave the room to bring that…
Page 30: Based on the graph, which of the following statement(s) are valid? (i) People in their twenties are the most…
Page 31: Without looking back at the chapter — which of the two formulas grows faster as t gets larger, and why?
Page 32: Place 8 knights on the chess board so that no knight attacks another. A knight moves in an ‘L-shape’. It can move…

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