C Curriculum Explorer
Mathematics·Number Representation & Place Value·procedural

Estimating by rounding

Use approximation through rounding to estimate answers and calculate possible resulting errors expressed using inequality notation a < x ≤ b; understand upper and lower bounds of rounded values

Suggested ages 12–14

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Evidence of understanding

  • Estimate the answer to a calculation by rounding all values appropriately
  • Calculate upper and lower bounds of a rounded measurement
  • Express error intervals using inequality notation

Assessment prompt

If a length is measured as 7 cm to the nearest cm, can Estimating by rounding say the actual length could be anywhere from 6.5 cm to 7.5 cm — understanding that rounding creates a range of possible values?

Standards alignment

KS3.Maths.Num.14GB · uk-nc-2013

Approximation and Estimation

The national curriculum in England: Key stages 1 and 2 framework document · Key Stage 3