Question

What is the least number which when increased by $3$ is exactly divisible by $27,35$, and $21$?

Answer 1

Let the number be $x$
Then, $x+3=$ LCM of $(27,35,21)$
LCM of $(27,35,21)=3\times 3\times 3\times 7\times 5=945$
$\therefore x+3$ = $945$
$\therefore x$ = $945-3$ $=$ $942$