Why does my child think 0.3 × 0.2 = 0.6?
Your child puts the decimal point in the wrong place, such as 0.3 × 0.2 = 0.6 instead of 0.06.
Why children do it
Children often keep the decimal point where it was in the question, as they do when adding. But multiplying by a number less than 1 makes things smaller: a tenth of a tenth is a hundredth. 0.3 × 0.2 is 3 × 2 = 6 hundredths, which is 0.06.
How to help at home
Count the decimal places in the question; the answer has as many. 0.3 × 0.2 has two, so it's 0.06.
The right way
Calculate: 0.3 × 0.5
- 3 × 5 = 15Multiply without the points.
- 0.15The two numbers had two decimal places between them, so the answer has two.
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