How do you subtract #\frac { 5} { 6} - \frac { 3} { 9}#?

1 Answer
Meave60
Dec 3, 2016

The answer is #1/2#.

Explanation:

The denominator must be the same in order to add or subtract fractions. So we look for the least common denominator (LCD). We list the multiples of each denominator and look for the smallest multiple that they have in common.

List the multiples of #6:# #6,12,color(red)(18),24...#
List the multiples of #9:# #9, color(red)(18), ...#

The LCD is #18#.

Now multiply each fraction by an #color(blue)("equivalent fraction")# that will give it the denominator #color(red)(18)#.

#5/6xxcolor(blue)(3/3)-3/9xxcolor(blue)(2/2)#

Multiply across.

#15/18-6/18=9/18#

Simplify.

#9/18=1/2#

Related questions
Impact of this question
538 views around the world
You can reuse this answer
Creative Commons License