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 21 by the denominator 8:
21 (numerator) ÷ 8 (denominator) = 2.63
As a result, you get 2.63 as your answer when you convert 1 13/8 (or 21/8) to a decimal.