Try some yourself

Activity 30

Carry out the following calculations, without your calculator.

  • (a) 3 × (60 + 70).

  • (b) (3 × 60) + 70.

  • (c) (70 − 60) ÷ 5.

Check your answers using your calculator.

Answer

  • (a) 3 × (60 + 70) = 3 × 130 = 390.

  • (b) (3 × 60) + 70 = 180 + 70 = 250.

  • (c) (70 − 60) ÷ 5 = 10 ÷ 5 = 2.