Rounding and truncating decimal numbers

Rounding decimal numbers

Round to tenth, to hundredth and to thousandth the following decimal number: $$2,3851$$

To tenth $\rightarrow 2,4$

To hundredth $\rightarrow 2,39$

To thousandth $\rightarrow 2,385$

So, when rounding off, for example, to tenth, we write only one decimal. If the following decimal is bigger than $0,05$ we round it up (as in the previous case), otherwise we round it down. That is, $2,38$ would be $2,4$, while $2,34$ would be $2,3$.

Truncating decimal numbers

Truncate to tenth, to hundredth and to thousandth the following number: $$2,3851$$

To tenth $\rightarrow 2,3$

To hundredth $\rightarrow 2,38$

To thousandth $\rightarrow 2,385$

As we can see, to truncate to tenth it is enough to write the number with a decimal digit, to truncate to hundredth with two decimal digits and so on.