Three numbers which are co-prime to each other are such that the product of the first two is 551 and that of the last two is The sum of the three numbers is:

A 75

B 81

C 85

D 89

Correct Answer: Option C

Since the numbers are co-prime, they contain only 1 as the common factor.

Also, the given two products have the middle number in common.

So, middle number = H.C.F. of 551 and 1073 = 29;

First number = (551/29) = 19;

Third number = (1073/29) = 37.

So, Required sum = (19 + 29 + 37) = 85.