Today’s problem — free all day, every step. Every day has one.
subtract money amounts
Calculate $20.00 − $12.75.
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The pattern behind it: Decimals and percentages
Keep place values and the whole visible while scaling decimals or finding a percentage.
In this one. Working in cents keeps the two decimal places exact.
How to spot it
The question offers two possible units for the same kind of measurement, such as cm or km, or asks to read a time or a percentage from a picture.
Common mistake
Children pick the unit that sounds familiar rather than the one that fits the object's size, or read a clock's hour and minute hands the wrong way round.
Try one like it
Standard add money amounts Calculate $3.75 + $2.48.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.