How do you convert 29.2987 (987 being repeated) to a fraction?

1 Answer
Mar 13, 2016

29.2bar(987) = 19513/666

Explanation:

Multiply by 10(1000-1) = 10000-10 to get an integer:

(10000-10)*29.2bar(987)

=292987.bar(987) - 292.bar(987)

=292695

The factor 10 is to shift the original number so that the repeating portion starts just after the decimal point. The factor (1000-1) is to further shift the number 3 places and subtract the original to cancel out the pattern that repeats every 3 digits.

Then dividing both ends by (10000-10) we find:

29.2bar(987) = 292695/(10000-10) = 292695/9990 = (color(red)(cancel(color(black)(15)))*19513) / (color(red)(cancel(color(black)(15)))*666) = 19513/666