Why does my child work out 150 km in 3 hours as 3 ÷ 150?
Your child divides the wrong way round for a rate, such as 150 km in 3 hours as 3 ÷ 150.
Why children do it
Children often divide whichever way round they're used to, rather than by what the answer means. A rate's name says which way: kilometres per hour is kilometres divided by hours, 150 ÷ 3, which is 50 km/h.
How to help at home
Say the rate's name: kilometres per hour means kilometres divided by hours.
The right way
A car travels 160 km in 4 hours. What is its average speed in km/h?
- 160 ÷ 4Distance divided by time.
- 4040 km for each hour.
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