How do you write the fraction #9/21# in simplest form?

2 Answers
Nov 28, 2016

Answer:

#3/7#

Explanation:

#9/21=(cancel(3)xx3)/(cancel(3)xx7)=3/7#

Nov 28, 2016

Answer:

#3/7#

Explanation:

We have to find a #color(blue)"common factor"# that will divide into both 9 and 21 and reduce the fraction.

In this case the lowest common factor is #color(red)(3)#

#rArr9/21=(9÷3)/(21÷3)=3/7#

This is usually written as shown below.

#9/21=cancel(9)^3/cancel(21)^7=3/7larrcolor(red)" in simplest form"#

This process is called #color(blue)"cancelling"#

A fraction is in #color(red)"simplest form"# when no other factor apart from 1 will divide into the numerator/denominator.