Why does my child think 3.2 × 10⁴ = 320 000?
Your child adds zeros to the end instead of moving the decimal point, such as 3.2 × 10⁴ = 320 000.
Why children do it
Adding zeros is how children multiply whole numbers by 10, so they add four zeros to the digits of 3.2. But multiplying by 10⁴ moves the decimal point four places: 3.2 becomes 32 000.
How to help at home
Ask them to move the decimal point one place for each power of 10, filling in zeros only where needed.
The right way
Write as an ordinary number: 4.5 × 10³
- 4500Move the decimal point 3 places to the right, and fill the gaps with zeros.
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