Ratio (age 10+)

MathematicsMultiplication & DivisionAges 10–11

Perform mental calculations including with mixed operations and large numbers, using strategies such as partitioning, compensation, and derived facts

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“Can your child work out a mixed calculation like '(200 × 6) + 350 − 75' entirely in their head — keeping track of each step without writing anything down?”

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Activity. Perform mental calculations including with mixed operations and large numbers, using strategies such as partitioning, compensation, and derived facts

What to notice. Mentally compute 45 × 8 by partitioning into 40 × 8 + 5 × 8 • Use known facts to derive 6.5 × 4 mentally • Solve a multi-operation mental calculation such as 250 × 3 + 500 and explain the strategy used

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Can your child work out a mixed calculation like '(200 × 6) + 350 − 75' entirely in their head — keeping track of each step without writing anything down?

Perform mental calculations including with mixed operations and large numbers, using strategies such as partitioning, compensation, and derived facts

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Check understanding

Mentally compute 45 × 8 by partitioning into 40 × 8 + 5 × 8
Use known facts to derive 6.5 × 4 mentally
Solve a multi-operation mental calculation such as 250 × 3 + 500 and explain the strategy used