L.C.M. of $10,15$ and $20$ is

The correct option is B

$60$

As we know that lowest common multiple is least multiples that are common between the numbers.

Prime factorisation of $10=2\times 5$

Prime factorisation of $15=3\times 5$

Prime factorisation of $20=2\times 2\times 5$

L.C.M $(10,15,20)=60$

Hence, L.C.M. of $10,15$ and $20$ is $60.$