Solution: 81/90 as a percent is 90%
Methods
Method 1 – Converting 81/90 Into a Percentage:
In a fraction, we can see how many “pieces” of a number are present (in the numerator) compared to how many pieces would make up the whole (the denominator). “Percent” means “per hundred”, which is like asking the question “how many pieces would there be if there were 100 pieces possible?”
For example, if we look at the percentage 50%, that means we have 50 pieces of the possible 100. Re-writing this in fraction form, we see 50/100.
We can start the process of converting a fraction into a percent, by figuring out how to adjust the fraction so that the denominator will be 100. First, divide 100 by the denominator:
100
90
=
1.111
\frac{100}{90} = 1.111
90 100 = 1.111
Then we can multiply both the numerator and denominator by this number:
81
∗
1.111
90
∗
1.111
=
90
100
\frac{81*1.111}{90*1.111} = \frac{90}{100}
90 ∗ 1.111 81 ∗ 1.111 = 100 90
This works because multiplying both the numerator and the denominator by the same number is like multiplying it by 1. (1.111 / 1.111 = 1)
Re-writing the result as a percentage, we can see that 81/90 as a percentage is 90%.
Method 2 – Converting 81/90 Into a Percentage Using Decimals:
Another common way to convert a fraction into a percentage is to first convert the fraction into a decimal. To convert 81/90 into a percentage, you would first convert 81/90 into a decimal by dividing the numerator by the denominator:
81
90
=
0.9
\frac{81}{90} = 0.9
90 81 = 0.9
Once you have converted the fraction into a decimal, you can simply multiply by 100 to get the percentage:
0.9 x 100 = 90
And there you go! Now we can see that 81/90 as a percentage is 90%, the same way we did with the first method.
Now you know of two ways you can convert 81/90 into a percentage. The best way to master these methods is to practice! Grab a pencil and paper, and come up with some of your own fractions, and become a master at converting them into percentages!
Practice more percentage conversion problems
With a just a few more problems, you could become a pro at converting fractions to percentages. You can try some more right now!
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