Why does my child think −4 × (−3) = −12?
Your child gets the sign wrong when multiplying or dividing negative numbers, such as -4 × (-3) = -12.
Why children do it
A negative times a positive is negative, and many children stretch that to every case. The rule that two negatives make a positive feels made up until it's seen as a pattern: −4 × 2 = −8, −4 × 1 = −4, −4 × 0 = 0, so −4 × (−1) must be 4, and −4 × (−3) is 12.
How to help at home
Before working out the number, decide the sign: two negatives make a positive, one negative makes a negative.
The right way
Calculate: 8 × (−3)
- 8 × 3 = 24Work out the size first.
- −24The signs are different, so the answer is negative.
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