1. Percents and Proportions (6-6)

2. Finding Part of a Whole 0% part 65% n 100% 245 whole
part
65% n
100%
245
whole
65 = n : Write a proportion
65(245) = 100n : Write cross products
65(245) = 100n : Divide each side by 100
= n
65% of 245 is

3. Finding a percent N = 52: Write a proportion 100 60
60n = 100(52) : Write cross products
60n = 100(52) :Divide each side by 60
N = 86.6 repeating : Simplify
=86.7: Round
52 is approximately 86.7% of 60 0% n% 52
part
100% 60
whole

4. Finding a Whole Amount 46 = 207 : Write a proportion 100 n
46n = 100(207) : Write cross products
46n = 100(207) : Divide each side by 46
N = 450 : Simplify
207 is 46% of 450 0%
46%
207
part
100%
whole n

5. Key concepts on percents and Proportions
Finding the percent
What percent of 40 is 6?
N =
100% 40
Finding the part
What number is 15% of 40?
15 = n
Finding the whole
6 is 15% of what number?
15 = 6 n

6. Many word problems can be solved using the formula
“is over of equals percent over 100.”
We can use this relationship to set up equations and solve for the variable.
BACK

7. The 100 stays the same in all problems The number here is
already a percent, just
replace with the number
The value of
the is & of come
from the problem
Only 2 of the 3 values of is, of, and % will be given, the missing amount is were you will put the variable.
The 100 stays
the same in all
problems
BACK

8. Sixty-eight is 20% of what number?68 x

9. What number is 15% of 60? 15 x 60

10. 37 is what percent of 296? x 37
296

11. Story Problem
Population In 1950, the population of Alaska was about 128,535. That was about 20.5% of the population of Alaska in the year About how may people lived in Alaska in the year 2000?
20.5 = 128,535 : Write a proportion n
20.5n = 100(128,535): Write cross products
20.5n = 100(128,535) : Divide each side by 20.5
The answer you should get is: 627,000 people