How do you simplify #5/7 - 2/3#?

1 Answer
Aug 4, 2016

Answer:

#1/21#

Explanation:

#color(blue)("Two very important facts")#

#color(brown)("Fact 1")#
You can not #ul("directly")# add or subtract counts in fractions unless their 'size' indicators are the same.

#("count")/("size indicator")->("numerator")/("denominator")#

'......................................................................................

#color(brown)("Fact 2")#
Multiplying by 1 does not change the intrinsic value of something.

Multiply by 1 in some different form does not change the intrinsic value but #ul("does change the way it looks")#.

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Answering your question")#

#color(brown)((5/7xx1)-(2/3xx1))color(blue)(" "->" "(5/7xx3/3)-(2/3xx7/7)#

#=(5xx3)/(7xx3) - (2xx7)/(3xx7)#

#=15/21-14/21#

#(15-14)/21 = 1/21#