7th Grade Math

352 Percent

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.

Find the Tip

TIPPING A customer wants to tip 15% of

the restaurant bill. What will be the total

bill with tip?

Method 2 Add the percent of tip to 100%.

100% + 15% = 115% Add the percent of tip to 100%.

The total cost is 115% of the bill.

115% of $35 = 1.15 × $35 Write 115% as a decimal.

= $40.25 Multiply.

Method 1 Add the tip to the regular price.

First, find the tip.

15% of $35 = 0.15 × 35 Write 15% as a decimal.

= 5.25 The tip is $5.25.

$5.25 + $35 = $40.25 Add the tip to the bill.

The total cost of the bill with tip is $40.25.

b. TAXICAB Scott wants to tip his taxicab driver. If his commute

costs $15 and he wants to give the driver a 20% tip, what is the

total cost?

HAIRCUTS 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%.

19.75% of $20 = 0.1975 × 20 Write 19.75% as a decimal.

= 3.95 Multiply.

$20 + $3.95 = $23.95 Add.

Since $23.95 < $25, $25 is sufficient to cover the total cost.

c. SPA Find the total cost of a spa treatment of $42 including 6%

tax and 20% tip.

5"#-& 8"*5&35*.&Check

%"5& /6.#&3$0%&^004322

Herbed Salmon 16.25

35.00

Chicken Pasta 15.25

Iced Tea 1.75

Iced Tea

Total

1.75

THANK YOU

SAL’S BISTRO

Real-World Link

In a recent year, the

Internal Revenue

Service estimated

that Americans paid

$15.37 billion in tips.

RRR

Mental Math Mental Math 10% of a

number can be found by

moving the decimal one

place to the left.

10% of $20 is $2. So,

20% of $20 is $4.

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