Question

What does$0.9\mathrm{cm}$ mean? It is the same as ________millimetres. We can also say this is nine-tenths of a $\mathrm{cm}$. Right?

Answer 1

Meaning of $0.9\mathrm{cm}$

$0.9\mathrm{cm}=\frac{9}{10}\mathrm{cm}$ means $9\mathrm{cm}$ out of $10\mathrm{cm}$is considered.

Conversion:

Convert $0.9\mathrm{cm}$ into $\mathrm{mm}$

$$\begin{gathered} \because 1\mathrm{cm}=10\mathrm{mm} \\ \Rightarrow 0.9\mathrm{cm}=0.9\times 10\mathrm{mm} \\ \Rightarrow 0.9\mathrm{cm}=9\mathrm{mm} \end{gathered}$$

So,$0.9\mathrm{cm}$ is the same as $\underline{9\mathrm{millimetres}}$.

Hence, $9\mathrm{millimetres}$ is nine-tenths of a $\mathrm{cm}$ is a correct way of saying $0.9\mathrm{cm}$ in words.