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Year 7 Maths — Letters for numbers

Write simple algebraic expressions and work out their value.

Name: ________________________

Before you start

The scale is level. Move the weights about and see what keeps it that way.

38

Take the same amount off both sides and it stays level. Take it off one side only and the scale says so at once — which is the whole rule for solving an equation, felt before it is written down.

  1. 1.If a = 6, what is the value of a × a?

  2. 2.The scale is level and every box holds the same. What does one box weigh?

    The scale is balanced. Write what one box weighs.

    353

  3. 3.If y = 9, what is the value of 2y - 4?

  4. 4.If x = 4 and y = 3, what is the value of x + 2y?

  5. 5.Which expression means '5 more than x'?

    • a) x + 5
    • b) 5 - x
    • c) x - 5
    • d) 5x

  6. 6.Match each description to the expression that says the same thing.

    • 7 less than m
    • m shared equally between 7
    • 7 times m
    • 7 more than m
    • m + 7
    • 7m
    • m - 7
    • m ÷ 7

  7. 7.Add weights from the shelf until both sides are equal.

    Circle weights from the tray to make the scale level.

    127532

  8. 8.If x = 5, what is the value of x + 12?

Answer key — Year 7 Maths — Letters for numbers

  1. 1. 36
  2. 2. box = 5
  3. 3. 14
  4. 4. 10
  5. 5. a) x + 5
  6. 6. 7 less than m → m - 7; m shared equally between 7 → m ÷ 7; 7 times m → 7m; 7 more than m → m + 7
  7. 7. 5 on the right pan
  8. 8. 17