the sum of 3 numbers is 98 . if the ratio of the first to the second is 2 : 3 and that of the second to the third is 5 : 8 , then the second number is :  Select.
A) 20	B) 30	C) 38	D) 48	E) none of these

Rationale: a : b = 2 : 3 = 2 × 5 : 3 × 5 = 10 : 15 and b : c = 5 : 8 = 5 × 3 : 8 × 3 = 15 : 24 therefore , a : b : c = 10 : 15 : 24 ∴ a : b : c = 10 : 15 : 24 let the number be 10 x , 15 x and 24 x . then , 10 x + 15 x + 24 x = 98 or 49 x = 98 or x = 2 ⇒ second number = 15 x = 15 × 2 = 30 answer b
Answer: B