Question

The smallest number which when mutliplied by $2$ is divisible $12,16,18,21$ and $28$ is

• A. $504$
• B. $1008$
• C. $630$
• D. $1510$

Answer 1

The correct option is A $504$

Factors of 12 - 2 x 2 x 3

Factors of 16 - 2 x 2 x 2 x 2

Factors of 18 - 2 x 3 x 3

Factors of 21 - 3 x 7

Factors of 28 - 2 x 2 x 7

LCM - 2 x 2 x 2 x 2 x 3 x 3 x 7 = 1008

L.C.M. of $12182128=1008$

Required number $=\frac{1008}{2}=504$