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P5–P6 Branching

Today’s problem — free all day, every step. Every day has one.

Brown and white eggs — a farmer sells some of each

A farmer collected some eggs. of them were brown eggs and the rest were white eggs. After selling 60 white eggs and of the brown eggs, she had of the eggs left. How many eggs did the farmer sell?

One step of the worked solution to Brown and white eggs — a farmer sells some of each, drawn in pencil.
8 steps, drawn in pencil

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The pattern behind it: Branching

The second fraction is of one piece, not of the whole.

In this one. Turn "4/5 of the brown eggs" into a fraction of all the eggs — once the brown share left (1/8) is measured against the same whole as the 1/4 left altogether, the white share falls out by subtraction and the 60 lands on a known fraction of the total.

All of it$81books4/9 → $36the rest5/9 → $45a game1/3 of $45 = $15left$30

How to spot it

A second fraction arrives after the first and is attached to a piece rather than to the whole — 'of the remainder', 'of what was left', or 'of the ones that were red'.

Common mistake

Children take the second fraction of the original total instead of the piece it was named against, which makes the amount come out too big.

Try one like it

Standard A dress and a handbag — Mei's savings Mei spent $48 on a dress. This was 3/8 of her savings. After buying the dress, she spent 1/5 of the remaining savings on a handbag…
All 11 with this pattern →

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.