Question: is 1 divided by 7 a repeating decimal?
Answer: Done. The single repeating digit is 3. For 1/7, it's obvious that 9/7 has a remainder, as does 99/7 (and for k=3, 4 or 5 as well). But when we use (10^6)-1=999999, we arrive at the integer only quotient of 142857 (999999 / 7 = 142857).