Today’s problem — free all day, every step. Every day has one.
John's salary — rent, food and savings
John's salary is $3,200. He spends 40% on rent, 25% on food, and saves the rest. How much does he save each month?
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65 worked examples are free without a code, two from every pattern. No account, either way.
The pattern behind it: Units and parts
Cut one amount into equal shares. One number tells you what a share is worth.
In this one. Add the two spending percentages before doing any money arithmetic — then "the rest" is a single subtraction from 100%, instead of two separate amounts to work out and take away.
How to spot it
A single amount is split by a ratio, a fraction or a percentage. One extra number gives you the leftover, the difference, or the value of one share.
Common mistake
Children match the given number to the wrong number of shares, using the whole bar when the number covers only the leftover or the difference between two people's shares.
Try one like it
Standard Ayesha's book — pages left over the weekend Ayesha read 5/8 of a book over the weekend. She had 51 pages left to read. How many pages does the book have in total?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.