AFCAT Model Paper 5

Given:
a : b = 4: 3
b : c = 4: 5
Calculation:
Taking (LCM of 3 and 4) = 12
a : b = 16 : 12 and b : c = 12 : 15
⇒ a : b : c = 16 : 12 : 15
Let the three numbers be 16x, 12x and 15x
⇒ a2:b2:bc
⇒ (16x)2:(12x)2:(12x×15x)
⇒ 256 : 144 : 180 = 64 : 36 : 45
∴ The value of a2:b2:bc is 64:36:45.