Question

Find the last number which divided by $6,15$ and $18$ leaves remainder $5$ in each case.

Answer 1

Solution:

L.C.M. of $6,15and18$

$6=2\times 3$

$15=5\times 3$

$18=2\times 3\times 3$

L.C.M. of $6,15and18=2\times 3\times 3\times 5=90$

Now,

$5+90=95$

Hence, 95 is the least number which when divided by $6,15and18$ leaves a remainder $5$ in each case.