In a fraction with a denominator of 15, which value could the numerator be to produce a repeating decimal?
any number that is NOT divisible by 3
e.g. 347 is not divisible by 3, and 347/15 = 23.13333...
suppose the numerator is divisible by 3
then it could be written as 3k
and 3k/15
= 3k/(3*5)
= k/5, and dividing anything by 5 results in a single decimal answer.