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 140 by the denominator 40:
140 (numerator) ÷ 40 (denominator) = 3.5
As a result, you get 3.5 as your answer when you convert 3 20/40 (or 140/40) to a decimal.