Find the LCM of the following numbers:

(a) 9 and 4 (b) 12 and 5

(c) 6 and 5 (d) 15 and 4

Observe a common property in the obtained LCMs. Is LCM the product of two numbers in each case?

LCM – Least common multiple

The LCM of two numbers is the smallest number that is a multiple of both the numbers.

(a) 9 and 4

LCM = 2 × 2 × 3 × 3 = 36

(b) 12 and 5

LCM = 2 × 2 × 3 × 5 = 60

(c) 6 and 5

LCM = 2 × 3 × 5 = 30

(d) 15 and 4

LCM = 2 × 2 × 3 × 5 = 60

Yes, it can be seen that in each case, LCM of given numbers is the product of thses numbers. When two numbers are co-prime, their LCM is the product of those numbers. Also, in each case, LCM is a multiple of 3.