A fraction is converted to a decimal by dividing the numerator by the denominator. The result can have two forms; one with a fixed number of decimal digits and the other with a recurring digit.
For example 5/2 is converted to a decimal by diving 5 by 2. The result is 2.5
An example where the number of decimal digits is not fixed is 4/3. Here the result is 4/3 = 1.333... where 3 is the recurring digit.
There are several ways to change a fraction to a decimal.
One way is to divide the numerator by the denominator.
e.g. 3/7 = .43
If the fraction has a common denomator of 10, 100, 1000, etc., then simply find equivalent fractions. Using the numerator, move the decimal point one place to the left for tenths, two places to the left for hundredths. Three for thousandths, etc.
e.g. 5/25 x 4/4 = 20/100 = .2
Another way is to make a proportion by using this formula-
numerator/denominator = x/100
Cross-multiply to get the answer.
e.g. 8/9 = x/100, 9x = 800, x = 88, .88
Hope this helps.