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Q1. Anusha has to prepare for her Maths exam. She has to study for 8 hours per day to complete the entire syllabus in 10 days. But because she had some relatives visiting, she was unable to study for two entire days. Now for how many hours should she study to finish the syllabus in the remaining 8 days?

• 1) None
• 2) 9 hours
• 3) 11 hours
• 4) 10 hours

Solution

8 × 10 = 8 × x

Q2. If the weight of 5 sheets of paper is 20 grams, how many sheets of the same paper would weigh 1 kg?

Solution

It is clear that the number of sheets and their corresponding weight vary directly. Also 1 kg = 1000 grams. Writing the information in the table, we have Number of sheets 5 x Weight (in grams) 20 1000 Now, in case of direct variation the ratio remains constant, so we have Hence, number of sheets are 250.

Q3. The cost of 6 balls is Rs 42. What would be the cost of 10 balls, 15 balls and 20 balls? Write them in the form of a table.

Solution

The cost of 6 balls is Rs 42. We know that as the number of balls increases, the cost increases. Thus, they are directly proportional. Let the cost of 10 balls, 15 balls and 20 balls be x, y, and z respectively.   Quantity 6 10 15 20 Cost (in Rs) 42 x y z In case of direct proportion, the ratio of the two quantities remains constant. Therefore, On solving, we get, x = 70 y = 105 z = 140   Thus, we have: Quantity 10 15 20 Cost (in Rs) 70 105 140  

Q4. Anuradha had some chocolates. She ate 3 of them per day, and after 20 days, she had none left to eat. Now she wished that she had saved them for 30 days. How many chocolates should she eat per day? 

• 1) 1
• 2) None
• 3) 2
• 4) 3

Solution

3 × 20 = 30 × x 

Q5. 40 boys earn Rs 2000 in 20 days, how much will 50 boys earn in 24 days?

Solution

Money earned by 40 boys in 20 days = Rs 2000 Therefore, money earned by 40 boys in 1 day = Rs Thus, money earned by 1 boy in 1 day = So, money earned by 1 boy in 24 days = Rs 2.50 x 24 = Rs 60 Hence, money earned by 50 boys in 24 days = Rs 60 x 50 = Rs 3000.

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