1. 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

2. Objective(s)
Learn the easy way to calculate gratuity (a tip) at a restaurant (decimals)
Review adding decimals and finding the sum
Splitting the bill (mean or average)
Review check writing
Review rounding

3. 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.
If the food isn't good, the menu is sparse, the prices are outrageous, and/or the decor is appalling... all of this affects your dining experience, but is not the waiter's fault. If you're unhappy with it, don't patronize the restaurant again, or write a negative review somewhere.
Give the benefit of the doubt. If the service was not quite stellar, it may not be the waiter's fault. Unless your waiter was rude or neglectful, you might want consider the following:
Did the entire restaurant appear busy and understaffed? Less attentive service might be the result of poor management.
Mistakes in orders do happen, and it's hard to know if the waiter, chef or both were responsible. If your waiter works hard to fix a problem, it's kind to give him the benefit of the doubt.
Does your waiter seem new to the job? Waiting takes a lot of practice and skill; you might want to give a new waiter a bit of a break.

4. 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.
If you really like a certain establishment, add an extra 5% to what you would normally tip, or "side tip" your favorite servers/bartenders something extra. Since you will be there frequently, the staff will be happy to see you every time you walk in and will remember you as a good tipping customer, thus enhancing the overall experience for everyone, including yourself.
Even if the waiter was undoubtedly terrible, it is still good practice to leave a 10% tip. In many restaurants, tips are pooled and shared with other employees (e.g., food runners, bartenders, and bussers) who might have done their job well. 10% is enough to avoid punishing people who might not be at fault.[7]
Give feedback to management or the directly to the waiter instead of, or in addition to, leaving a low tip. Many customers leave poor tips regardless of service, so simply doing so may not convey the message intended. A low tip is no guarantee that service will improve in the future because staff may not know what made you unhappy or who was responsible. Not only will the manager be able to correct the situation, but you might also get a gift certificate out of it.[7][8]
If you're eating with small children and make a big mess, remember that staff will have to clean it up, and that this usually takes extra time. Consider leaving servers a little extra for this inconvenience. If the server is especially helpful with child-related issues during the meal, you might also wish to tip a little extra for that.

5. 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 be?
10% would be $4.683
$4.683 can then be rounded to the nearest tenth (4.70) or the nearest dollar ($5.00)

6. 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.
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

7. 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 (rounded to the nearest dollar).
4.68 rounds to $5.00
Double it ($5.00+$5.00), or ($5.00 x 2) = 10.00

8. 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.

9. 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 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

10. 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)

11. 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?

12. Homework
Create a story problem and calculate the total bill (without tax) and a 10%, 15%, and 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.
=16.00
10% tip 1.60 rounded to the nearest dollar 2.00
15% tip ( ) $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!

13. Sources http://www.wikihow.com/Tip-Your-Server-at-a-Restaurant
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