Question

what least number should be subtracted from 1222 to get a number exactly divisible by 42?

Answer 1

First we divide 1222 by 42 as;
$$\begin{gathered} 42)1222(29 \\ 84 \\ \overline{382} \\ 378 \\ \overline{4} \end{gathered}$$
So when we divide 1222 by 42, we get the remainder 4.
Therefore the least number that should be subtracted is 4.