The HCF and LCM of two numbers m and n are respectively 5 and 210. If m + n = 75, then 1/m + 1/n is equal to	Choose the most appropriate option
A) 1 / 14	B) 3 / 35	C) 5 / 37	D) 2 / 35	E) none

Rationale: "answer we have , m x n = 5 x 210 = 1050 â ˆ ´ 1 / m + 1 / n = ( m + n ) / mn = 75 / 1050 = 1 / 14 correct option : a"
Answer: A