Today’s problem — free all day, every step. Every day has one.
Books read — a bar graph of five children
A bar graph shows the number of books read by five children. Emma read 12, Lucas read 8, Mia read 15, Noah read 10, and Olivia read 5. What is the average number of books read?
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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. Reading values off a graph and averaging them are two separate jobs — copy the five numbers out of the picture first, then it is only ever total ÷ how many.
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.