Why does my child think 2^x = 32 gives x = 16?
Your child divides to solve an exponential equation, such as 2^x = 32 giving x = 16 instead of x = 5.
Why children do it
For most equations children meet, dividing undoes multiplying, so it's what they reach for. But 2^x means 2 multiplied by itself x times, and x counts the 2s: 2, 4, 8, 16, 32 is five of them, so x = 5. Checking 2^16 shows it's far too big.
How to help at home
Ask them to check by multiplying out: is 2^16 really 32? Then count the 2s instead: 2, 4, 8, 16, 32.
The right way
Solve: 2^x = 32
- 2 × 2 × 2 × 2 × 2 = 32Five 2s multiply to make 32.
- 5So x = 5.
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