Question

By rounding off 21.7 to nearest whole number would obtain .

Answer 1

Last digit of a whole number is it's unit place digit.

Here the first digit to be dropped, i.e., 7 is more than 5.

$\therefore$ The last digit to be kept, i.e., 1 is increased by 1.
$1+1=2$

Rounded off number is 22.

Also by plotting 21.7 on a number line, we observe that 21.7 is closer to 22 than 21.