Question

Expresss $3cm68mm$ as centimetre $\left(cm\right)$ using decimals.

Answer 1

We know that,$10mm=1cm$.

We are going from smaller unit to greater unit. So, we will divide the smaller unit to get the bigger unit.

$$\begin{gathered} 3cm68mm=3cm+68mm \\ 3cm68mm=3cm+\frac{68}{10}cm \\ 3cm68mm=3cm+6.8cm \end{gathered}$$

Therefore, $3cm68mm=9.8cm$.