What is 2.4 as a percentage?

2 Answers
Mar 31, 2016

#2,4xx100%=240%#

Mar 31, 2016

Answer:

240%. With a very detailed explanation about how percentage works.

Explanation:

Note that 2.4 is #2+4/10#

So as an improper fraction this is #24/10#

#color(blue)("Using short cut method:")#

Converting to a percentage #->24/10xx 100% = 24xx10%=240%#
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Viewed another way:

The whole number 2 can be written as #10/10+10/10#

So the whole thing is:# 10/10+10/10+4/10#

So this gives you 2 lots of #100%# plus #(4/10xx100)%#
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#color(blue)("From first principles")#

Percentage is just another way of writing fraction. The only difference is the bottom number (denominator) is fixed at 100.

So you write #x/100#. This is the equivalent of #x%#

So how do we convert our #color(green)(24/10)# into percentage fractional format. We use the principle of ratios.

We need to change the denominator from 10 into 100.

So if we multiply by 1 but in the form of #color(red)(1=10/10)# we have

#color(green)(24/10)xxcolor(red)(10/10)" "=" "color(green)((24color(red)(xx10))/(10color(red)(xx10)) color(blue)(" "=" " 240/100= 24%)#

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