Today’s problem — free all day, every step. Every day has one.
Ahmad's walk to school and back
Ahmad walks from home to school at 5 km/h and returns at 4 km/h. If the school is 2 km away, what is his average speed for the whole journey?
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65 worked examples are free without a code, two from every pattern. No account, either way.
The pattern behind it: An average is a total
Turn the average back into a total before doing anything with it.
In this one. Average speed is total distance ÷ total time, never the average of the two speeds — the slower leg takes longer, so it counts for more.
How to spot it
The word 'average' appears alongside a group being split into two parts, or two separate journeys or trips being combined into one overall figure.
Common mistake
Children average two averages directly, such as averaging two speeds or two group averages, without weighting by how many, or how long, each part actually covers.
Try one like it
Standard A bakery's week — average daily sales A bakery recorded its sales over 5 days: $42, $48, $55, $51 and $44. What was the average daily sales amount over the 5 days?The 33 problem patterns
All 33 patterns, one to a page — the 19 behind Primary 5 and 6 word problems, and the skills the younger years are built on. The bar model, how to spot it in the question, and the mistake children make. A booklet you can print. Free.
A PDF, and a note when new solutions go up.