13, a, b, c are four distinct numbers and the HCF of each pair of numbers (13, a) ; (13, b) ; (13, c) is 13, where a, b, c are each less than 60 and a < b < c. What is the value of $$\frac{{{\text{a}} + {\text{c}}}}{{\text{b}}}?$$

A. 3.5

B. 2

C. 5

D. 4.5

Answer: Option B

Solution(By Examveda Team)

Four distinct numbers 13, a, b, c are given
HCF of (13, a) : (13, b) : (13, c) = 13 and a < b < c
It is clear that
a = 26
b = 39
c = 52
$$\eqalign{ & {\text{Then, }}\frac{{{\text{a}} + {\text{c}}}}{{\text{b}}} \cr & = \frac{{26 + 52}}{{39}} \cr & = \frac{{78}}{{39}} \cr & = 2 \cr} $$