The ratio of three numbers is 1:2:5 and the sum of their squares is 4320. The sum of the numbers is?	Pick one
A) 10	B) 12	C) 15	D) 14	E) 9

Rationale: "let the numbers be x , 2 x , 5 x then , x ^ 2 + 4 x ^ 2 + 25 x ^ 2 = 4320 30 x ^ 2 = 4320 x ^ 2 = 144 x = 12 answer is b"
Answer: B