1. Percent increase

2. Percent Change
The ratio comparing a change in a quantity to the original amount.
Percent change= amount of change/original amount

3. Percent Increase Write an equation Write/solve a proportion
Percent increase = amount of increase/original amount
Write/solve a proportion
Amount of increase/original amount = percent increase (%) / 100

4. Find the percent increase from 12 to 15
Equation
Amount of increase / original amount = percent increase
15-12 =3  amount of increase
Original amount = 12
3/12 = .25 = 25%
Proportion
Amount of increase / original = percent increase / 100
3/12=x/100
12x=300
X=25

5. Find the percent increase from 40 to 45

6. Amount of Profit Cost- original amount spent for an item
Profit- the money gained when an item is sold at cost
To find the amount of profit:
Multiply the original cost by the percent profit

7. Write/solve a proportion Profit / original = percent profit (%) / 100
A company buys microwave ovens for $200 each then sells each at a gain of 15%. What is the company’s profit?
Write an equation
P = .15 x 200
P = $30.00
Write/solve a proportion
Profit / original = percent profit (%) / 100
P/200 = 15/100
3000 = 100p
P = $30

8. Selling Price
Selling price- the amount for which the item is sold. Add the profit to the cost to find the selling price.
A video dealer imports large flat screen TVs for $1200 each. The dealer then sells each TV at a profit of 30%. What is the selling price?
SP = $ (30% of 1200)
SP = $ (.30 x 1200 = $360)
SP = $ $360
SP = $1560

9. Sales tax rate x marked price = sales tax Set up/solve a proportion
Sales tax- amount of tax added to the marked price by state or local government.
Write an equation
Sales tax rate x marked price = sales tax
Set up/solve a proportion
Sales tax / marked price = sales tax rate (%) / 100

10. Equation .06 x 29.95 = 1.797 = $1.80 Proportion t/29.95 = 6/100
A calculator is priced at $29.95 with a sales tax of 6%. What is the amount of sales tax to the nearest cent?
Equation
.06 x = = $1.80
Proportion
t/29.95 = 6/100
100t=179.70
T = $1.80

11. Discount Discount = discount rate x list price
Sale price = list price – discount
Discount rate = amount of discount / list price

12. Markup Markup = list price – wholesale price
Markup rate = markup / wholesale price
Markup rate is expressed as a percent

13. Commission-Amount of money earned for selling goods or services.
Equation
Commission = commission rate x total sales
Write/solve proportion
Commission/total sales =commission rate (%) / 100

14. 6% commission on $25,000 in sales
.06 x 25,000 =
x/25,000 = 6/100 =

15. 6% commission on $25,000 in sales
.06 x 25,000 = $1500
x/25,000 = 6/100 = $1500

16. $1755 earned on $92,000 in sales
C x 92,000 = 1755
1755/92000 = x/100

17. $1755 earned on $92,000 in sales C x 92,000 = 1,755 1755/92000 = x/100
C=about 1.9%
1755/92000 = x/100

18. Simple Interest Principal (p)- amount of money borrowed or deposited
Interest (I)- amount earned or paid in exchange for the use of money
Rate of interest (r)- percent of interest earned or paid
Time (t)- how long in years the principal is borrowed or left on deposit.
Simple interest- interest earned or paid only on the principal for a stated period of time

19. Time is expressed in years or fractional part of a year
Interest = principal x rate x time
I=prt
Time is expressed in years or fractional part of a year

20. Find the simple interest (I): $800 at an annual rate of 8% for 9 months
I=prt
I=(800)(.08)(9/12)
I= $48

21. Compound Interest
Compound interest- interest paid on the principal and on the interest accumulated to date.
balance