Why does my child take 3/5 of $40 to share it in the ratio 3:5?
Your child treats one part of a ratio as a fraction of the total, such as taking 3/5 of $40 to share it 3:5.
Why children do it
A ratio like 3:5 looks like the fraction 3/5, so children use it as one. But 3:5 means 3 parts for one and 5 parts for the other: 8 parts in all. The first share is 3/8 of the total, which is $15.
How to help at home
Draw the ratio as boxes: 3:5 is 3 boxes and 5 boxes, so 8 boxes share the total.
The right way
Share $50 in the ratio 1:4. How much is the smaller share?
- 1 + 4 = 5There are 5 shares in all.
- 50 ÷ 5 = 10One share is $10.
- $10The smaller part is 1 share.
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Start the free checkRelated mistakes
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