Any value that you can write as a fraction can also be written as a decimal and any value that can be written as a decimal can be written as a fraction. Here are a few examples:
.4 = 4/10 .5 = 5/10 .3 = 3/10 .7 = 7/10
Write the digit(s) to the right of the decimal point over a multiple of ten with the same number of zeroes as the number of places in the decimal to the right of the decimal point. For instance, .43 has two digits to the right of the decimal and so it gets written as 43/100 as a fraction.
.42 = 42/100 .55 = 55/100 .33 = 33/100 .25 = 25/100
Now you get to try a few for yourself.