Why does my child think 2/3 = 11/12?
Your child adds to make an equivalent fraction instead of multiplying, such as 2/3 = 11/12.
Why children do it
To get from 3 to 12, many children think "add 9", then add 9 to the top as well, because adding is what they reach for first. But an equivalent fraction is the same amount cut into more pieces: the bottom was multiplied by 4, so the top must be too. 2/3 is 8/12.
How to help at home
Ask what the bottom was multiplied by, then do the same to the top.
The right way
Solve: 3/4 = x/12
- 12 ÷ 4 = 3The bottom was multiplied by 3.
- 3 × 3 = 9So multiply the top by 3 too.
- x = 9The missing top.
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