How do you simplify the fraction 15/36?

1 Answer
Feb 27, 2017

Showing a little trick
5/12

Explanation:

color(blue)("The trick")

Consider the numbers given:

Adding the digits of the 15 of 15/36

1+5=6 and 6 is exactly divisible by 3 thus so is 15

Adding the digits of the 36 of 15/36

3+6=9 and 9 is exactly divisible by 3 thus so is 36
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color(blue)("Answering the question")

15/36-=(15-:3)/(36-:3) = 5/12

The -= means 'equivalent to'

5 is a prime number so we can not simplify any further.