SOLUTION: i'm confused as to how to do these problems. for example : what is 80% of 14? or 15 is what percent of 45?

Question 240769: i'm confused as to how to do these problems. for example : what is 80% of 14? or 15 is what percent of 45?
Found 2 solutions by edjones, jsmallt9:
Answer by edjones(8007) (Show Source): You can put this solution on YOUR website!
14*.8=11.2
.
Let the percent = 100x
45x=15
x=15/45=1/3
1/3 * 100=100/3 % = 33 1/3 %
.
Ed
Answer by jsmallt9(3758) (Show Source): You can put this solution on YOUR website!
There are several keys to these problems:
The "is" translates into an equals sign.
The "of" translates into a multiplication symbol: "*".
The unknown number is "x" (or what ever variable you prefer).
Use the fraction or decimal version of a percent. For example, 15% us 15/100 (which reduces to 3/20) or 0.15.
If the unknown is the percent use x/100.

Let's try this on your problems:
What is 80% of 14?
This translates into:

To find x all we have to do is simplify the right side. 80/100 reduces to 4/5:
}
Multiplying 4/5 and 14 we get:

As a mixed number this is . As a decimal this is 11.2. So 80% of 14 is

15 is what percent of 45?
This translates into:

Simplifying the right side we get:

To solve for x we will multiply both sides by the reciprocal of 9/20:

This simplifies to

As a mixed number this is . As a decimal this is 33.333.... (repeating 3's). So 15 is % of 45.
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