Question

The product of two numbers is 1600 and their HCF is 5. The LCM of the numbers is 

(a) 8000 

(b) 1600 

(c) 320 

(d) 1605

Answer 1

(c) 320 

Let the two numbers be x and y. 

It is given that: 

x × y = 1600 

HCF = 5 

We know, 

HCF × LCM = x × y 

⇒ 5 × LCM = 1600

⇒ ∴ LCM = \(\frac{1600}5\) = 320