Calculate a tip at a restaurant
Small groups
Take a couple minutes to discuss what you know about tipping at a
restaurant
Share your findings
Objective(s)
 Learn the easy way to calculate gratuity (a tip) at a restaurant
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(decimals)
Review adding decimals and finding the sum
Splitting the bill (mean or average)
Review check writing
Review rounding
First Evaluate your Service
 Evaluate your service. The key is to objectively judge the
service, and the service alone. The service itself should be
judged on:
How the food matched with your order,
Whether the food was hot and fresh from the kitchen,
How attentive the server was to your needs,
How quickly your empty dishes were taken away,
How quickly it took to get your check and have your payment
processed, and
 Whether the server's demeanor was courteous and professional.
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Determine the tip
 The general guideline is 20% for excellent service, 15% for solid
service, and 10% for bad service. On average, people tip 18%.
 For our lessons today we will be working with 10%, 15%, and 20% tips.
 Future decimal and percent lessons will explore the easy way to
calculate an 18% tip! (hint double the tax). Tax in our state is between 8
and 9%.
 Now that you know what percentage you want to pay, it's time to
actually crunch the numbers.
To calculate a 10% tip (the easy way)
 Remember we would leave a 10% tip if we felt the service was
bad.
 An easy way to figure a 10% tip is to move the decimal point
one space to the left.
For example, if the bill is $35.00
10% would be $3.50
What would 10% of 46.83 be?
10% would be $4.683
$4.683 can then be rounded to the nearest tenth (4.70) or the
nearest dollar ($5.00)
To Calculate a 20% tip (the easy way)
 An easy way to figure a 20% tip is to move the decimal point of the cost to find
10%, and then double it.
For example, if the bill is $35.00
10% would be $3.50 if we double it ($3.50+$3.50) or ($3.50 x2)
a 20% tip would be $7.00.
Note: If it is difficult for you to add change in your head you can
round to the nearest dollar. For good service round up, bad service
round down. A 20% tip indicates they provided good service so we will
round up.
For example, if the bill is $35.00
10% would be 3.50, we can round that to $4.00 and then double it ($4.00 +
$4.00), or ($4 x 2) = $8.00
20% tip would be $8.00
Try calculating a 20% tip
What would 20% of 46.83 be?
10% would be $4.683 (rounded to the nearest tenth $4.70)
Double it ($4.70+ $4.70) or ($4.70 x 2) =$9.40
Note: If it is difficult for you to add change in your head you can
round to the nearest dollar. For good service round up, poor
service round down. A 20% tip indicates they provided good service
so we will round up.
20% of 46.83 (rounded to the nearest dollar).
4.68 rounds to $5.00
Double it ($5.00+$5.00), or ($5.00 x 2) = 10.00
To Calculate a 15% tip (the easy way)
 An easy way to figure a 15% tip is to move the decimal point of the cost to find
10%, and add half of that amount.
For example, if the bill is $35.00
10% would be $3.50 if we cut that in half we get $1.75
($3.50+$1.75) = 5.25
a 15% tip would be $5.25.
Note: If it is difficult for you to add change in your head you can
round to the nearest dollar. For good service round up, bad service
round down. A 15% tip indicates they provided good service so we will
round up.
Note: If it is difficult for you to add change in your head you can
round to the nearest dollar. For good service round up, poor
service round down. A 20% tip indicates they provided good service
so we will round up.
What would 15% of 46.83 be (round to the nearest dollar)?
10% would be $4.683 (rounded to the nearest dollar $5.00)
Add 10% ($5.00) + half of 10% (2.50)
($5.00+ $2.50) =7.50
$29.26
10% of $29.26 =2.926
2.926 rounds to $3.00, half of $3.00 is $1.50
($3.00+$1.50) = $4.50
In your group discuss and answer the
following questions
 What is :
 10% of a bill that totals $61.32
 15% of a bill that totals $25.55
 20% of a bill that totals $ 36.81
(round each bill total to the nearest dollar)
In your groups discuss and answer the
following questions
 You and your group are eating out at The Firehouse Café today!
 Each person chooses what they will eat and drink.
 Go around the table and share your order with your group
 As each person shares their order you write it down (the item and
the cost)
 What is the total bill for your group? (today we will not add tax)
 Calculate a 10% tip, a 15% tip, and a 20% tip (round to the
nearest dollar).
 If you were to split the bill equally with the members of your
group what would your portion of the bill be?
Homework
 Create a story problem and calculate the total bill (without tax) and a 10%, 15%, and
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20% tip. Round to the nearest dollar.
Write a check to pay for your meal, include the cost of the meal and the tip. Round to
the nearest dollar (will you leave a 10%, 15%, or 20 % tip?)
Explain why you left a 10%, 15%, or 20% tip
Due tomorrow.
Example:
Sally went to Red Robin for lunch. She had a Pepsi $2.95, potato Skins $7.95, and a side
Salad $4.95.
3.00+8.00+5.00=16.00
10% tip 1.60 rounded to the nearest dollar 2.00
15% tip (2.00+1.00) $3.00
20% tip ($2.00+$2.00), or ($2.00 x 2) =$4.00
I left a 20% tip because my hostess was very kind and provides great customer service. For
example she was attentive to our needs. She refilled my Pepsi before I had to ask!
Sources
 http://www.wikihow.com/Tip-Your-Server-at-a-Restaurant
 http://www.ehow.com/how_5364600_quickly-calculate-
tip.html
 http://lenpenzo.com/blog/id1618-are-you -smarter-than-a5th-grader-then-calculate-this-bill...