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 4700 by the denominator 80 (which you can enter in any calculator):
4700 (numerator) ÷ 80 (denominator) = 58.75
And finally, you get 58.75 as your answer when you convert 57 140/80 (or 4700/80) to a decimal.