A fraction with a 10 or a multiple of 10 as its denominator, can be easily expressed in the form of a decimal. Using the decimal formula, the number of decimal places in the answer is equal to the number of zeros in the multiple of 10 in the denominator. a10=0. aa100=0.0aa1000=0.00a. a a 100 = 0.0 a a 1000 = 0.00 a.