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Class 7 Maths — The unitary method

Find the value of one thing first, then scale it to any number — and tell direct proportion from inverse.

Name: ________________________

  1. 1.If 5 notebooks cost ₹150, what do 8 notebooks cost? Give just the number.

  2. 2.More workers finish the same job in less time. That relationship is called...

    • a) direct proportion
    • b) no proportion at all
    • c) inverse proportion
    • d) a ratio in its simplest form

  3. 3.A machine fills 350 bottles in 5 minutes. How many bottles does it fill in 8 minutes?

  4. 4.A car travels 240 km in 4 hours. How far does it travel in 1 hour, in kilometres?

  5. 5.One pen costs ₹12. Match each number of pens to what they cost. Give the cost as a plain number.

    • 3 pens
    • 5 pens
    • 7 pens
    • 10 pens
    • 120
    • 36
    • 84
    • 60

  6. 6.A car travels 240 km in 4 hours. At the same speed, how far does it travel in 7 hours, in kilometres?

  7. 7.12 identical bricks weigh 30 kg. What do 20 of those bricks weigh, in kilograms?

  8. 8.Which of these pairs are in direct proportion?

    • a) The number of pens bought and the total cost
    • b) The speed of a car and the time it takes on a fixed journey
    • c) The number of workers and the days needed to finish a job
    • d) The number of taps filling a tank and the time it takes

Answer key — Class 7 Maths — The unitary method

  1. 1. 240
  2. 2. c) inverse proportion
  3. 3. 560
  4. 4. 60
  5. 5. 3 pens → 36; 5 pens → 60; 7 pens → 84; 10 pens → 120
  6. 6. 420
  7. 7. 50
  8. 8. a) The number of pens bought and the total cost