2. Bellwork
Alonso plans to buy a new kayak that costs $2,100. But when he buys the kayak, it actually costs more because he lives in a county where there is a 7% sales tax.
You can find the amount of tax on an item by multiplying the price by the tax percentage.
1. Circle the amount below that shows the amount of tax Alonso will pay for the kayak.
$350 $235 $147
2. Use the amount of tax from number 1to fill in the receipt at the right.
Then find the total cost Alonso will pay for the kayak.
3. Multiply 1.07 and $2,100. How does the result compare to your answer in number 2?
4. On Alonso’s kayaking trip, hiring a guide costs $50. Alonso wants to give the guide a 10% tip. Explain how to find the amount of the tip.

3. Sales Tax and total cost
Sales tax is an additional amount of money charged on items that people buy. The total cost of an item is the regular price plus the sales tax.

4. Example 1
Drew wants to buy exercise equipment that costs $140 and the sales tax is %. What is the total cost of the equipment?
Method 1: Add sales tax to the regular price.
First, find the sales tax.
Let t, represent the sales tax.
Part = percent x whole
t = x 140
t = 8.05
Next, add the sales tax to the regular price.
$ $140 = $148.05

5. Example 1
Drew wants to buy exercise equipment that costs $140 and the sales tax is %. What is the total cost of the equipment?
Method 2: Add the percent of tax to 100%.
100% +5.57% = %
Let t, represent the total.
Part = percent x whole
t = x 140
t =
The total cost of the exercise equipment is $148.05

6. On your own
What is the total cost of a sweatshirt if the regular price is $42 and the sales tax is %?

7. Tips and markups
A tip or gratuity is a small amount of money in return for a service. The total price is the regular price of the service plus the tip.
A store sells items for more than it pays for those items. The amount of increase is called the markup. The selling price is the amount the customer pays for an item.

8. Example 2
A customer wants to tip 15% on a restaurant bill that is $35. What will be the total bill with tip?
Method 1: Add the tip to the regular price.
First, find the tip.
Let t, represent the tip.
Part = percent x whole
t = 0.15 x 35
t = 5.25
Next, add the tip to the regular price.
$ $35 = $40.25

9. Example 2
A customer wants to tip 15% on a restaurant bill that is $35. What will be the total bill with tip?
Method 2: Add the percent of tip to 100%.
100% +15% = 115%
Let t, represent the total.
Part = percent x whole
t = 1.15 x 35
t = 40.25
Using either method, the total cost of the bill with tip is $40.25

10. Example 3
A haircut costs $20. Sales tax is 4.75%. Is $25 sufficient to cover the haircut with tax and a 15% tip? Sales tax is 4.75% and the tip is 15%, so together they will be 19.75%. Let t represent the tax and tip. Part = percent x whole t = (20) t = 3.95 $ = $23.95 Since $23.95 < $25, $25 is sufficient to cover the cost.

11. On your own
A) Scott wants to tip his taxicab driver 20%. If his commute costs $15, what is the total cost?
B) Find the total cost of a spa treatment of $42 including 6% tax and 20% tip.

12. Example 4
A store pays $56 for a GPS navigation system. The markup is 25%. Find the selling price. First, find the markup. Let m represent the markup. Part = percent x whole m = .25 (56) m = 14 Next, add the markup to the amount the store pays. $14 + $56 = $70 The selling price of the GPS navigation system is $70.

13. On your own
A store pays $15 for a portable basketball backboard and the markup is 40%. What is the selling price?