What is the sum of the smallest and second-smallest positive integers a satisfying the congruence 27a = 17 (mod 42)?

27a = 17 (mod 42)

I don't believe that this is actually possible.

Since both 27 and 42 are multiples of 3, 27a also has to be a multiple of 3.

However, 17 is not a multiple of 3.

=^._.^=

good spotting Catmg