Question

Find LCM : 12, 45, 75.​

Answer 1

Given:

12, 45, 75

To find:

The LCM of the given number

By prime factorisation of the given numbers, we get,

12 = 2 * 2 * 3 = 2² * 3

45 = 3 * 3 * 5 = 3² * 5

75 = 3 * 5 * 5 = 3 * 5²

Now,

Here is a short and easy trick to find the LCM after prime factorisation.

Choose the common number between the numbers with their highest power,  and multiply the remaining

So,

LCM of 12, 45, 75 = 3² * 2² * 5² = 900

Hence,

The LCM of (12, 45, 75) is 900.

More Information,

To find the HCF,

First, do prime factorisation of the numbers and choose the common number with their lowest power.