Why does my child think 15% of $80 is $1200?
Your child forgets the 100 in a percentage, such as 15% of $80 = $1200.
Why children do it
Multiplying the percentage by the amount is the right idea, but 15% means 15 out of 100, so it also needs dividing by 100: 15% of $80 is $12. An answer bigger than the amount you started with is the clue, since 15% of something is always less than it.
How to help at home
Ask whether the answer makes sense: 15% of $80 must be less than $80.
The right way
Find 40% of $180.
- 40/100 × 18040% as a fraction, times the amount.
- $7240 × 180 is 7200, and 7200 ÷ 100 is 72.
Find out where your child is
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Start the free checkRelated mistakes
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