a+b

[kanha81]

If a and b are positive integers, what is the value of a + b ?

1) a/b = 5/8
2) greatest common divisor of a and b is 1

Please explain

[iamcste]

If a and b are positive integers, what is the value of a + b ?

1) a/b = 5/8
2) greatest common divisor of a and b is 1

Please explain

IMO C

Individually we dont know a and b hence a+ b is not known

when we know HCF is 1 and ratio of a/b= 5/8, this means a=5 and b=8, a+b=13

[DeepakR]

I think it is C.)

1. a/b=5/8 so a can be 5,10 etc and b can be 8, 16 etc..insufficient

2. GCD of a and b = 1 but a can be 2 or 3 and be can be 3 or 4 insufficient.

Combining we can say that a=5 and b=8 is the only value that satisfies.

- Deepak