The aim of the video is to show how to reduce a fraction by factoring out prime numbers that are common to both the numerator and the denominator. The example shown in the video is 27/21. The number 27 can be achieved by multiplying 3 by 9 and the number 21 is the result of 3 multiplied by 7. The common factor, therefore in both the numerator and the denominator is 3. 3 on the top divided by 3 on the bottom is 1 and so this can be removed without affecting the value of the fraction, leaving 9/7. Therefore, the original fraction of 27/21 can be reduced to 9/7.

**It’s Black Friday week on WonderHowTo!** Don’t miss out on all of the big sales in the Gadget Hacks and Null Byte shops. And if you’ve been wanting to take some classes without going into debt, check out our best deals on online courses for a variety of skill sets. Don’t miss out on these huge discounts:

**See Gadget Hacks’s top 10 BF sales on online courses (up to 99% off) >**

**See Null Byte’s top 13 BF sales on online courses (up to 99% off) >**

## Be the First to Comment

## Share Your Thoughts