using percent. warm-up: get a calculator find the percent of each number. 1)25% of 200 2)22% of 40...
TRANSCRIPT
Using Percent
Warm-up: Get a calculator • Find the percent of each number.
1) 25% of 200
2) 22% of 40
3) 63% of 89
4) 112% of 24
5) Jenny sold 380 boxes of cookies for her Girl Scout troop. 55% of the cookies sold were oatmeal cinnamon boxes. How many boxes of oatmeal cinnamon cookies did she sell?
Objectives
As a learner, I will…– Solve percent problems that involve discount,
tips and sales tax.
*** Application Notes #12***
Common Uses of PercentsDiscounts An amount that is subtracted from the
regular price of an item
Discount = price * discount rate
Total cost = price – discount
Tips An amount added to a bill for service
Tip = bill * tip rate
Total cost = bill + tip
Sales tax An amount added to the price of an item
Sales tax = price * sales tax rate
Total cost = price + sales tax
Helpful Hints
• You can find 10% of a number by moving the decimal point one place to the left
• You can find 1% of a number by moving the decimal point two places to the left
• You can find 5% of a number by finding half of 10% of the number
Finding Discounts
Step 1: Calculate the discount
Discount = price * discount rate
Step 2: Subtract the discount from the regular price
Total cost = price – discount
Finding Discounts
Example 1: A music store sign reads “10% off the regular price.” If Nichole wants to buy a CD whose regular price is $15, about how much will she pay for her CD after the discount?
Finding Discounts
• You try…
A clothing store is having a 25% off sale. If Angela wants to buy a sweater whose regular price is $20, how much will she pay for the sweater after the discount?
Finding Tips
• Step 1: Calculate the Tip
Tip = bill * tip rate
• Step 2: Add the tip to the bill price
Total cost = bill + tip
Finding Tips
• Example 2: Leslie’s lunch bill is $14.00. She wants to leave a tip that is 15% of the bill. How much should her tip be? What will be the total amount of money she will pay?
Finding Tips
• You try…
Ben’s dinner bill is $8.00. He wants to leave a tip that is 20% of the bill. How much should his tip be? What will be the total amount of money he will pay?
Finding Sales Tax
• Step 1: Calculate the Sales Tax
Sales tax = price * sales tax rate
• Step 2: Add the sales tax to the price
Total cost = price + sales tax
Finding Sales Tax
• Example 3: Marc is buying a scooter for $80.00. The sales tax rate is 6%. How much will the sales tax be? How much will the total cost of the scooter be?
Finding Sales Tax
• You try…
Ann is buying a $30 pair of jeans. The sales tax rate is 7%. How much will the total cost be?