Question

Hcf and lcm of 2 numbers 9 and 360 if one number is 45 , find the number

Answer 1

Answer:

72

Step-by-step explanation:

In general, for any two positive integers a and b, their product is equal to the product of their hcf and their lcm.  That is:

a b = hcf(a,b) lcm(a,b)

To see why this is true, just think about how you work out the lcm and the hcf when you have the prime factorizations of a and b.

Here, we have a = 45, hcf(a,b) = 9 and lcm(a,b) = 360.  Therefore

b = hcf(a,b) lcm(a,b) / a = ( 9 ) ( 360 ) / 45 = 360 / 5 = 72.