How do you simplify #(2/5+1/5)-3/10#?

1 Answer
Nov 25, 2016

Answer:

#3/10#

Explanation:

#color(blue)("Important fact 1")#

Multiply by 1 and you do not change the value. However 1 comes in many forms. So you can change a the way a fraction looks without changing its actual value.

#color(blue)("Important fact 2")#
A fraction consists of #("count")/("size indicator") -> ("numerator")/("denominator")#

You can not directly add or subtract the counts unless the size indicators are the same

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#" "color(green)(=[2/5color(red)(xx1)] color(white)(.)" "+" "[1/5color(red)(xx1)]" "-" "3/10#

#color(white)(..)color(green)(=[2/5color(red)(xx2/2)]" " +" "[1/5color(red)(xx2/2)]" "-" "3/10#

#color(white)(.)" "=[4/10 ]color(white)(...)" "+" "color(white)(...)[2/10]" "-" "3/10#

#" "=6/10" "-" "3/10#

#" " =(6-3)/10#

#" " = 3/10#

color(white)(.)