Question #6489d

1 Answer
Mar 3, 2017

The question does not state if you require the amount reduced by or the final figure left after the reduction.

#65%" of "80=52#

#80-52=28#

Explanation:

#color(blue)("Preamble")#

There are two things to remember hear.

1: We are talking about a change that is a reduction. So the answer #" "#is a negative value.

2: The symbol % is a bit like units of measurement and that is worth #" "1/100# So 65%#->65xx1/100 = 65/100#

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#color(blue)("Answering the question")#

This is a reduction so the amount it is reduced by is: #65/100xx80#

There are several paths that can be followed now but they all lead to the same point.

With practice you could some of this in your mind.

Write as #65xx80/100 " "->" "65xx(80-:10)/(100-:10) = 65xx8/10#

#=65/100xx8" "=" "6.5xx8#

#6xx8=" "48#
#1/2xx8=" "ul(color(white)(.)4)larr" add"#
#" "52#

But this a reduction so the answer to this part is: #-52#
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