Subject: General Aptitude · Chapter: H.C.F. and L.C.M. of Numbers · Exam: 2010 · Marks: · Difficulty:
If the sum of two numbers is 36 and their H.C.F. and L.C.M. are 3 and 105 respectively, the sum of the reciprocals of the two numbers is
(a)$\frac{2}{35}$
(b)$\frac{3}{35}$
(c)$\frac{4}{35}$
(d)None of these
Answer
Answer (as printed): C
Explanation
Let the numbers be $a$ and $b$. Then, $a+b=36$ and $a b=3 \times 105=315$. ∴ Required sum $=\frac{1}{a}+\frac{1}{b}=\frac{a+b}{a b}=\frac{36}{315}=\frac{4}{35}$.
Explanation as extracted from the printed page; notation may be imperfect.