How do you simplify #3/5×(-1/4 - 1/6) ÷ (-7/3 + 5/4)#?

1 Answer
Oct 19, 2017

#3/5 xx (-1/4-1/6) -:(-7/3+5/4)=color(blue)(3/13#

Explanation:

Simplify:

#3/5 xx (-1/4-1/6) -:(-7/3+5/4)#

Follow the order of operations: parentheses, exponents, multiplication and division left to right, addition and subtraction left to right.

Simplify the parentheses first.

#(-1/4-1/6)# must have a common denominator. The least common denominator (LCD) can be found by listing the multiples of #4# and #6#.

#4:##4,8,color(red)12,16...#

#6:##6,color(red)12...#

LCD#=##color(red)12#

Multiply both fractions by a fraction equal to #1#, so that each will have the same denominator. For example, #5/5=1#. This way, the values don't change.

#(-1/4xxcolor(teal)3/color(teal)3-1/6xxcolor(magenta)2/color(magenta)2)#

Simplify.

#(-3/12-2/12)=(-5/12)#

Return #(-5/12)# to the original expression.

#3/5 xx (-5/12) -:(-7/3+5/4)#

Simplify #(-7/3+5/4)#.

Follow the same procedure as with #(-1/4-1/6)#.

LCD#=##12#

#(-7/3xxcolor(green)4/color(green)4+5/4xxcolor(red)3/color(red)3)#

Simplify.

#(-28/12+15/12)=-13/12#

Return #(-13/12)# to the original equation.

#3/5 xx (-5/12) -:(-13/12)#

Multiply #3/5# and #-5/12#.

#-15/60-:(-13/12)#

Divide #-15/60# and #-13/12#.

When dividing by a fraction, invert the fraction and multiply.

#-15/60xx-12/13#

Simplify.

#180/780#

Reduce by dividing the numerator and denominator by #60#.

#(180-:60)/(780-:60)=3/13#