How do you simplify #7/8 + 11/14 -5/6#?

1 Answer
EZ as pi
May 2, 2018

#139/168#

Explanation:

In order to add or subtract fractions you have to have the same denominator:

Let's use prime factors to find the #LCM#. It is not an obvious one.

#" "8 = 2xx2xx2#
#" "6 = 2 color(white)(x.xxxx)xx3#
#" "14 = ul(2color(white)(x.xxxxxxx)xx7)#
#LCM = 2xx2xx2xx3xx7 = 168#

#7/8+11/14-5/6#

#(7/8 xx 21/21)+(11/14 xx12/12)-(5/6xx28/28)#

#=(147+132-140)/168#

#=139/168#

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