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 124 by the denominator 6 (which you can enter in any calculator):
124 (numerator) ÷ 6 (denominator) = 20.67
And finally, you get 20.67 as your answer when you convert 4 100/6 (or 124/6) to a decimal.