Why does my child solve x/3 = 5 as x = 5/3?
Your child divides to undo a division, instead of multiplying.
Why children do it
x/3 means x divided by 3, so undoing it means multiplying by 3. Children who divide again are copying the operation they can see, rather than undoing it. x/3 = 5 means a third of x is 5, so x = 15.
How to help at home
Ask what undoes dividing. Multiplying does: x/3 = 5 becomes x = 5 × 3.
The right way
Solve: x/3 + 4 = 9
- x/3 = 5Subtract 4 from both sides.
- x = 15Multiply both sides by 3.
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