A fraction is usually split into two parts: the first part is the number on top, called the numerator; and the second part is the number on the bottom, called the denominator. These are both separated by a line called the “divisor line”. We can use the division method help to solve this question: to get a decimal, simply divide the numerator 215 by the denominator 2 (which you can enter in any calculator):
215 (numerator) ÷ 2 (denominator) = 107.5
And finally, you get 107.5 as your answer when you convert 100 15/2 (or 215/2) to a decimal.