Rounding to whole numbers and tens

In many calculations you will be expected to round off your answer to the nearest whole number or to the nearest ten.

Example

Write \(38.7\) to the nearest whole number

Number line showing 38, 38.5 and 39.  38.7 is marked with a bead.

\(38.7\) lies between \(38\) and \(39\).

\(38.7\) is nearer to \(39\) than \(38\)

So, \(38.7 = 39\) (to the nearest whole number)

Now try the example questions.

Question

Write \(6.5\) to the nearest whole number

\(6.5\) lies between \(6\) and \(7\).

Number line from 6 to 7, showing 6.5 as mid-way.

\(6.5\) lies mid-way between \(6\) and \(7\).

When this happens always round up

So, \(6.5 = 7\) (to the nearest whole number)

Question

Round \(103.4\) to the nearest ten.

\(103.4\) lies between \(100\) and \(110\)

Number line from 100 to 110, showing 105 as midway.  A bead marks 103.4.

\(103.4\) is nearer to \(100\) than \(110\)

So, \(103.4 = 100\) (to the nearest ten).