How do you change 0.452 into a percent and how do you round it to the nearest tenth of a percent?

3 Answers
Oct 22, 2016

0.4520.452 is 45.2%45.2%.

Explanation:

To change any decimal to a percent, you multiply the decimal by 100100..

0.452 * 100 = 45.2%0.452100=45.2%

In order to round to the nearest tenth, you examine the value in the hundredths place to determine whether or not the number in the tenths place will be kept or rounded up. However, there is no hundredths place in this case, so you are not able to round.

Amendment:

The above method of changing a decimal to a percent is the "easily remembered" method. It is based on the combination of several properties and definitions.

First, a percent is is part of one whole unit (or item, or total, etc.). Therefore, 100%100% is equal to 11.

The number 11 is the Multiplicative Identity. Remember that the Identity Property of Multiplication states that multiplication by the Multiplicative Identity (11) does not change the value of the original number. Algebraically stated, this is a * 1 = aa1=a.

Also, remember that any number has multiple forms. In this case, let's consider some equivalent forms of the number 11.
1 = 3/3 = (x + 7)/(x + 7) = 100%1=33=x+7x+7=100%
All four of these previous representations are equivalent in value. The Substitution Property of Equality allows us to use 100%100% in place of 11 when applying the Identity Property of Multiplication. Therefore, multiplying a decimal by 100%100% does not change its value, only its form.

And so, the more correct representation of the process shown in the original explanation is:

0.452 * 100% = 45.2%0.452100%=45.2%

If my earlier explanation was too simplistic or mislead anyone, I apologize.

Oct 22, 2016

0.452 = 452/1000 = 45.2/100 = 45.2%0.452=4521000=45.2100=45.2%

Explanation:

Decimals and percentages are interchangeable without any working at all. They are just different ways of writing the same thing.
Here are some examples.

25/100 = 25 " hundredths" = 25% = 0.2525100=25 hundredths=25%=0.25

Percentages are out of 100 and the second decimal place represents hundredths.

0.16 = 16/100 = 16%0.16=16100=16%

7% = 7/100 = 0.077%=7100=0.07

135% = 135/100 = 1.35135%=135100=1.35

4.5% = 4.5/100 = 45/1000 = 0.0454.5%=4.5100=451000=0.045

0.452 = 452/1000 = 45.2/100 = 45.2%0.452=4521000=45.2100=45.2%

It is already correct to one tenth of a percent (the first place holder after the decimal point.)

Oct 23, 2016

45.2%45.2% to the nearest tenth of a percent.

Explanation:

Think of 0.4520.452 as " "0+4/10+5/100+2/1000 0+410+5100+21000

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Consider the "4/10)Consider the 410

If we multiply it by 1 but in the form of 1=10/101=1010 we have

" "[4/10color(magenta)(xx1)]" "->" "[4/10color(magenta)(xx10/10)]" " =" " 40/100 [410×1] [410×1010] = 40100

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Putting it back together")Putting it back together

So we can write 0.4520.452 as " "0+40/100+5/100+2/1000 0+40100+5100+21000

Which is the same as 45/100+2/100045100+21000
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Consider the "2/1000)Consider the 21000

This can be written as 2/(100xx10)2100×10 which if we cancel out gives

" "(cancel(2)^(0.2))/(100xxcancel(10)^1)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Putting it back together")

So we can write 0.452 as " "45/100+0.2/100" "=" "45.2/100

color(brown)("Another way of writing "1/100" is %")
color(brown)("That way % is the unit of measurement worth " 1/100)

So 0.452" is equivalent to "45.2/100" " ->" " 45.2xx1/100" "->""45.2%
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Note that 0.2 -> 2/10 but this number is part of the percentage so it is already to the nearest tenth of a percent.