The easiest way to approach this problem is to find an equation for the nth term of the sequence. Here the first term is 58 and the common difference is 3; that is, each term is equal to the previous term, plus 3. The appropriate equation is thus:
a(n) = a(1) + 3(n-1). Check. What is a(2)? Find 58 + 3(1). It's 61, and correct.