Question

Find the LCM of $12$ and $14$.

• A. $24$
• B. $84$
• C. $36$
• D. $72$

Answer 1

The correct option is B $84$

Prime factorisation of $12$ and $14$ is as follows:
$12=2\times 2\times 3$
$14=2\times 7$

For LCM of numbers, we multiply all the factors by considering only the common factors once.

In the above case, LCM is $=2\times 2\times 3\times 7=84.$
Here, $2$ is comman factor for both number.
Hence, it is taken once, and the remaining factors, including the extra $2,$ are considered to find the LCM.