A degree of accuracy shows how precise a number or measurement is.  E.g. to the nearest cm, nearest 10, 1 s.f., etc

Degrees of accuracy

Maths

Checking understanding of rounding

Securing understanding of rounding

Rounding to three decimal places

Rounding to any number of decimal places

Rounding integers to one significant figure

Rounding integers to significant figures

Rounding decimals to significant figures

Estimating numerical calculations

Checking by estimating

Truncating

Overestimating vs underestimating

Rounding errors

Inequality notation to express error

Using inequality notation for errors in calculations

Problem solving with estimation and rounding

In this unit, pupils have learnt how to round to a given number of decimal places or significant figures and explored the effect of using rounded numbers for calculations. In the future unit, pupils will investigate the bounds and perform calculations to determine a best/worst case scenario.

The prior unit on place value allowed pupils to develop the skills needed to estimate and round values. By understanding the value of each digit, pupils can determine what other values are close to the original value. This unit continues the exploration of the infinite nature of sets of numbers.

This unit helps pupils understand rounding to different decimal places, and significant figures. Pupils will also learn how to truncate numbers and understand the contexts in which these skills are useful. The unit ends will an exploration of rounding and inequality errors.

Estimation and rounding

A {{ }} of accuracy shows how precise a number or measurement is.

The average size of a secondary school in 2024 was 1050.  This number is most likely to have been rounded to which degree of accuracy?

The average temperature in the UK in 2024 was 10.93°C.  This is most likely to have been rounded to which degree of accuracy?

Match each situation to the most appropriate degree of accuracy.

Use the exchange rate £1:$1.27 to convert $6.95 into pounds.  Give your answer to an appropriate degree of accuracy.

Use your calculator to evaluate $$1.27 - \sqrt{15}\over16.8 + 0.06$$.  Give your answer to an appropriate degree of accuracy.

A degree of accuracy shows how precise a number or {{ }} is.  For example, to the nearest cm, to the nearest 10 or to 1 significant figure. 

Match each number to the correct statement.

Round 0.00600736 to 3 significant figures.

Degrees of accuracy

Lesson outcome