1. Warm Up
Estimate.
1. 20% of 602
out of 264
3. 151% of 78
out of 0.95
Possible answers:
120
50%
120
30%

2. commission rate  sales = commission
commission: a fee paid to a person who makes a sale.
commission rate: a percent of the selling price.
commission rate  sales = commission
Often salespeople are paid a commission plus a regular salary.

3. Example 1: Finding Commission Amounts
A real-estate agent is paid a monthly salary of $900 plus commission. Last month he sold one condominium for $65,000, earning a 4% commission on the sale. How much was his commission? What was his total pay last month?
commission rate  sales = commission
4%  $65,000 = c
0.04  65,000 = c
2600 = c
commission + salary = total pay
$ $900 = $3500

4. Sales tax: the tax on the sale of an item or service.

5. Example 2: Finding Sales Tax Amounts
If the sales tax rate is 6.75%, how much tax would Adrian pay if he bought two CDs at $16.99 each and one DVD for $36.29?
CD: 2 at $ $33.98
DVD: 1 at $ $36.29
$70.27
 =
$4.74

6. Example 3: Finding the Percent of Earnings
Anna earns $1500 monthly. Of that, $ is withheld for Social Security and Medicare. What percent of Anna’s earnings are withheld for Social Security and Medicare?
Think: What percent of $1500 is $114.75?
114.75
1500 n
100 =
n  1500 = 100 
1500n = 11,475
11,475
1500 n =
n = 7.65
7.65%

7. Example 4: Finding Total Sales
A furniture sales associate earned $960 in commission in May. If his commission is 12% of sales, how much were his sales in May?
Think: $960 is 12% of what number?
Let s = total sales
960 = 0.12  s
960
0.12
= s
8000 = s
$8000

8. Lesson Quiz
1. Every month, Gillian makes $1600 plus an 8.9% commission on sales. If her sales last month totaled $18,400, what was her total pay?
2. The sales tax is 5.75%, and the shirt costs $20. What is the total cost of the shirt?
3. Sheridan has a yearly income of $39,650, and he is advised to invest $4500 every year. What percent of his income should he invest, to the nearest tenth of a percent?
4. If you earn a 4% commission, how much would your total sales have to be to make a commission of $115? $
$21.15
11.3%
$2875