The whole number 625 can be expressed as the fraction 625/1, because any number is equal to itself divided by 1. However, the decimal value 0.625 can be expressed as the fraction 5/8.

Any whole number can be expressed in terms of a fraction a/b, where a and b are whole numbers and b is not zero. For any whole number a, its fractional form is a/1. In the case of 625, its fractional form is 625/1.

A more common math question is how 0.625 can be expressed as a fraction. Determine the fractional form in several steps. Manipulate a number without changing the value by multiplying it by a form of 1; in this case, multiplying by a fraction a/a, where a is any nonzero number. If one multiplies 0.625 by 1000/1000, this action removes the decimal point and yields the value 625/1000. Next, this fraction should be simplified to lowest terms by dividing the numerator and denominator by common factors.

The values 625 and 1000 have a common factor of 25; dividing both the numerator and denominator by 25 yields 25/40. The numbers 25 and 40 have a common factor of 5; dividing 25 and 40 each by 5 yields 5/8. The fraction 5/8 is in lowest terms, meaning the numerator and denominator have no other common factors greater than one.