A fraction is written in terms of two parts: the number on top is called the numerator and the number on the bottom is called the denominator. We can use the division method to solve this question. To get a decimal, simply divide the numerator 135 by the denominator 31:
135 (numerator) ÷ 31 (denominator) = 4.35
As a result, you get 4.35 as your answer when you convert 3 42/31 (or 135/31) to a decimal.