Complete the sum

Find the number that completes the sum. 12 × 8 = 66 + ( ? )

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The answer is E. Work out the complete side first: 12 × 8 = 96. The other side must also come to 96. So ask: 66 add what makes 96? 96 − 66 = 30. Check it: 66 + 30 = 96. The answer is 30. The most common slip is giving the total of the first side as the answer. Check your answer by putting it back in.

Find the number that completes the sum. 9 × 2 = 28 − ( ? )

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The answer is D. Work out the complete side first: 9 × 2 = 18. The other side must also come to 18. So ask: 28 take away what leaves 18? 28 − 18 = 10. Check it: 28 − 10 = 18. The answer is 10. The most common slip is giving the total of the first side as the answer. Check your answer by putting it back in.

Find the number that completes the sum. 8 + 16 = 168 ÷ ( ? )

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The answer is B. Work out the complete side first: 8 + 16 = 24. The other side must also come to 24. So ask: 168 divided by what makes 24? 168 ÷ 24 = 7. Check it: 168 ÷ 7 = 24. The answer is 7. Both sides of the = sign must come to the same amount, like a balance.

Find the number that completes the sum. 13 + 21 = 45 − ( ? )

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The answer is C. Work out the complete side first: 13 + 21 = 34. The other side must also come to 34. So ask: 45 take away what leaves 34? 45 − 34 = 11. Check it: 45 − 11 = 34. The answer is 11. Always work out the side with no gap first. That number is what the other side has to make.

Find the number that completes the sum. 30 − 8 = 11 × ( ? )

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The answer is D. Work out the complete side first: 30 − 8 = 22. The other side must also come to 22. So ask: 11 times what makes 22? 22 ÷ 11 = 2. Check it: 11 × 2 = 22. The answer is 2. Always work out the side with no gap first. That number is what the other side has to make.

Find the number that completes the sum. 7 × 7 = 60 − ( ? )

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The answer is E. Work out the complete side first: 7 × 7 = 49. The other side must also come to 49. So ask: 60 take away what leaves 49? 60 − 49 = 11. Check it: 60 − 11 = 49. The answer is 11. Both sides of the = sign must come to the same amount, like a balance.

Find the number that completes the sum. 27 − 14 = 2 + ( ? )

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The answer is C. Work out the complete side first: 27 − 14 = 13. The other side must also come to 13. So ask: 2 add what makes 13? 13 − 2 = 11. Check it: 2 + 11 = 13. The answer is 11. Read the sign before the brackets carefully: a × needs a different working from a +.

Find the number that completes the sum. 88 ÷ 8 = 44 ÷ ( ? )

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The answer is C. Work out the complete side first: 88 ÷ 8 = 11. The other side must also come to 11. So ask: 44 divided by what makes 11? 44 ÷ 11 = 4. Check it: 44 ÷ 4 = 11. The answer is 4. Always work out the side with no gap first. That number is what the other side has to make.

Find the number that completes the sum. 12 × 5 = 10 × ( ? )

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The answer is D. Work out the complete side first: 12 × 5 = 60. The other side must also come to 60. So ask: 10 times what makes 60? 60 ÷ 10 = 6. Check it: 10 × 6 = 60. The answer is 6. Always work out the side with no gap first. That number is what the other side has to make.

Find the number that completes the sum. 43 − 20 = 161 ÷ ( ? )

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The answer is B. Work out the complete side first: 43 − 20 = 23. The other side must also come to 23. So ask: 161 divided by what makes 23? 161 ÷ 23 = 7. Check it: 161 ÷ 7 = 23. The answer is 7. Read the sign before the brackets carefully: a × needs a different working from a +.

Find the number that completes the sum. 41 − 17 = 20 + ( ? )

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The answer is B. Work out the complete side first: 41 − 17 = 24. The other side must also come to 24. So ask: 20 add what makes 24? 24 − 20 = 4. Check it: 20 + 4 = 24. The answer is 4. The most common slip is giving the total of the first side as the answer. Check your answer by putting it back in.

Find the number that completes the sum. 23 − 4 = 34 − ( ? )

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The answer is D. Work out the complete side first: 23 − 4 = 19. The other side must also come to 19. So ask: 34 take away what leaves 19? 34 − 19 = 15. Check it: 34 − 15 = 19. The answer is 15. Both sides of the = sign must come to the same amount, like a balance.

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Complete the sum

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