# The LCM of two positive no’s is 168 and their product is 504. what is the difference in their squares ?

The LCM of two positive no’s is 168 and their product is 504. what is the difference in their squares?

A. 175

B. 216

C. 9

D. 135

### **Answer : **D. 135...

504 = 2*2*2*3*3*7 = 8*3*3*7 = 24*21

168 = 2*2*2*3*7

It means 3 will come in both the numbers as 3 is coming once in LCM but coming as 9 in product.

so possible numbers are 24 and 21.

Now the difference of the square of these numbers is a^2-b^2 = (a+b)(a-b)

= (24+21)(24-21)

= 45(3)

= 135