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P3 P5 fraction foundations

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add related fractions

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5/8

One step of the worked solution to add related fractions, drawn in pencil.
5 steps, drawn in pencil

The pattern behind it: P5 fraction foundations

Translate division into a fraction, then calculate exactly with mixed and improper fractions.

In this one. Related denominators make an equivalent common unit; only then can numerators be combined.

2/3 of 3/4 is 6/12whole6/12 = 1/2

How to spot it

Two fractions with different denominators to add or compare, or a mixed number to calculate with, point here.

Common mistake

Children add or compare the numerators straight away without rewriting the denominators to match first, treating a third plus a sixth as two sevenths.

Try one like it

Standard add related fractions Calculate 1/3 + 1/6.
All 14 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.

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