Question

Express $21cm6mm$ as centimeters using decimals

Answer 1

Step 1

Convert the millimeter part into the centimeter

We know that

$$\begin{gathered} 1cm=10mm \\ \Rightarrow 1mm=\frac{1}{10}cm \\ \Rightarrow 6mm=\frac{6}{10}cm=0.6cm \end{gathered}$$

Step 2

Add both centimeter parts

$21cm+0.6cm=21.6cm$

Hence $21cm6mm$ can be represented as $21.6cm$