Question

Write the short form of the following as a decimal number.

$400+20+1+0.8+0.01+0.009$

Answer 1

We have,

$400+20+1+0.8+0.01+0.009=\left(4\times 100\right)+\left(2\times 10\right)+\left(1\times 1\right)+\left(8\times \frac{1}{10}\right)+\left(1\times \frac{1}{100}\right)+\left(9\times \frac{1}{1000}\right)$

Here, the place value of$4=400$, the place value of$2=20$, the place value of$1=1$, the place value of$8=\frac{8}{10}$, the place value of$1=\frac{1}{100}$, and the place value of $9=\frac{9}{1000}$

So, In decimal form, $4$ is at hundreds, $2$is at tens place, $1$is at ones,$8$ is at tenths,$1$ is at hundredths, and $9$is at thousandths place.

Hence, the decimal form is $421.819$