lesson
Keep the parts the same size
1 · Learn
Fractions with the same denominator have equal-sized parts. Add or subtract the number of parts and keep their size unchanged.
Two sevenths plus three sevenths is five sevenths. We do not add the denominators, because the pieces are still sevenths.
2 · Worked example
I shade six eighths, then remove two eighths of shading. Four eighths remain.
3 · Your turn
Calculate 3/8 + 2/8 and 7/8 − 4/8.
Check your answer
5/8 and 3/8.
4 · Apply your learning
Use a strip with equal boxes to model each calculation before writing it.
Adult guidance and safety
Use objects or a drawn model before relying on a rule. Explain each step, check the units and revisit with varied examples. An adult can read the instructions without supplying the answer.
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