Question

Evaluate the least common multiple of $21$ and $28.$

Answer 1

Few multiples of $21$ and $28$ are:
$21\times 1=21$
$21\times 2=42$
$21\times 3=63$
$21\times 4=84$

$28\times 1=28$
$28\times 2=56$
$28\times 3=84$
$28\times 4=112$

The least common multiple is $84.$