1. Percentage applications
Today’s Lesson:
What:
Percentage applications
Why:
. . . so I can solve several different types of percentage problems, including consumer applications, using the percent proportion formula.

2. What is the percent proportion formula?

3. The Percent proportion formula . . .
% part “is”
whole “of” =
We can use the above formula to solve ANY type of percentage problem. WHY??? Because, using this formula allows us to find the missing percentage, find the missing part, or find the missing _________________________.
We place ____________ in the correct position, according to what we need to find.
whole
x (variable)

4. Solving for the percent . . .
How do we set the proportion up??? Like this . . .
5 out of 85 is what percent?
𝒙 𝟏𝟎𝟎 = 𝟓 𝟖𝟓
Find 25% of 75:
𝟐𝟓 𝟏𝟎𝟎 = 𝒙 𝟕𝟓
20 is 10% of what number?
𝟏𝟎 𝟏𝟎𝟎 = 𝟐𝟎 𝒙
Solving for the percent . . .
Solving for the part . . .
Solving for the whole . . .

5. there were 40 total questions, how many did Collin answer correctly?
Real-Life Scenarios:
1) Collin scored an 88% on the test. If
there were 40 total questions, how
many did Collin answer correctly?
x ≈ 35 questions

6. Jane scored a 94% on the test
Jane scored a 94% on the test. If she answered 47 questions correctly, how many total questions were on the test?
x = 50 questions

7. On the Unit 8 Test, Holly got 40 questions correct out of 45 total questions. What was her percentage score?
x ≈ 89%

8. Things for a consumer to consider are:
Consumer applications . . .
A consumer is someone who ________________________ goods/ services at a variety of stores/businesses.
Things for a consumer to consider are:
Taxes (_________ to the purchase)
Discounts (____________ from the purchase)
Tips (__________ to the purchase)
Using the percent proportion formula--tax, discount, and tip problems always involve finding the part out of the total ! So, x will always be in the _________ position!
purchases
add
subtract
add
part

9. $38.15 your purchase is $54.50. There is a
Tip: Add
Tax: Add
Discount: Subtract
Store Scenarios:
The sub-total (original price) of
your purchase is $ There is a
30% discount. What is the sale price?
Sale price means price AFTER the discount, so this is a TWO-STEP problem.
Step 1: Find the discount using
the % proportion.
Step 2: Subtract the discount!
Step 1:
Step 2: Subtract discount
from original amount!
𝟑𝟎 𝟏𝟎𝟎 = 𝒙 𝟓𝟒.𝟓
$ $ = $38.15
1,635 = 100x
100
100
x = $16.35
$38.15

10. This is asking for tax only, so it just a ONE-STEP problem!
Tip: Add
Tax: Add
Discount: Subtract
The sub-total (original price) of your
purchase is $ There is a 5%
sales tax. What is the tax only?
This is asking for tax only, so it just a ONE-STEP problem!
$4.91

11. This is asking for the TOTAL, so it is a 2-step problem!
Tip: Add
Tax: Add
Discount: Subtract
The sub-total (original price) of your
purchase is $ The sales tax is
5%. What is your total?
This is asking for the TOTAL, so it is a 2-step problem!
$78.54

12. This is asking for the TIP only, so it is a ONE-STEP problem!
Tip: Add
Tax: Add
Discount: Subtract
Restaurant scenarios:
Your bill at a restaurant is $ You want to leave a 15% tip. How much is the tip?
This is asking for the TIP only, so it is a ONE-STEP problem!
$3.90

13. This is asking for the TOTAL, so it is a TWO-STEP problem!
Tip: Add
Tax: Add
Discount: Subtract
5) Your bill at a restaurant is $ You
want to leave an 18% tip. How much is
the total bill?
This is asking for the TOTAL, so it is a TWO-STEP problem!
$51.92

14. Wrap-it-up/summary: What is the percent proportion formula?
% part “is”
whole “of” =

15. END OF LESSON