To turn the decimal 0.15 into a fraction, we put 15 as the numerator of the fraction and the denominator would be 100 since there are 2 numbers that are after the decimal.
Notice that is not in lowest terms. We can divide both the numerator and the denominator of the fraction by our greatest common factor which is 5.
15 ÷ 5 = 3
100 ÷ 5 = 20
Therefore, 0.15 can be written as the fraction 3/20, which is in lowest terms.