Question

If the LCM of two num is 105 and HCF is 3 and one of the number is 15 than whats the other number.

Answer 1

lcm × hcf = 15 x
105×3/15 = x
21=x

Answer 2

First you need to factorise 105 .

You get factors 3,5,7.

Now, the first number is 15 i.e. 3×5=15

So, 105÷15=7

But, it is given that HCF is 3 and 7 does not have 3 as a factor.

Therefore, we multiply 3 to 7 i.e. 3×7=21

So,21 is the required number.

Now, let us check the answer once.

LCM of 15 and 21 =105

HCF of 15 and 21 =3

So, the answer is 21.

Hope this helps you.