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Checking your answer is correct

  • Subtraction can be checked by addition, and addition can be checked by subtraction:

    • To check 82 - 37 = 45, you could add 45 and 37 and see if you get 82.

      To check 56 + 31 = 87, you could take 31 away from 87 and see if you get 56.

  • Division can always be checked by multiplication, and multiplication can be checked by division:

    • To check 81 ÷ 3 = 27, you could multiply 27 by 3 and see if you get 81.

      To check 9 x 12 = 108, you could divide 108 by 9 and see if you get 12.

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