I came across the following question on the BBC website; Convert 0.272727 to a fraction. It was a multiple choice question so I could test each possible answer by dividing the numerator by the denominator until I got the right one. But it made me wonder how I could have answered it had it not been multiple choice. I could have got as far as 272,727/1,000,000 but then how would I know how to reduce that? I know to look for common factors but would struggle with such a large number. There was another example also; convert 0.6121212 to a fraction.