Percents

Percentages in Real Life

Calculating tips

If you've eaten at a restaurant, you've probably left a tip for your server. A tip is a small amount of money that you add to your bill when someone gives you service. The amount of a tip is usually a percentage of the total cost. For example, you might leave a fifteen percent tip at a restaurant for average service.

Let's say you eat at a restaurant with some friends. The bill comes to $12.04, and you'd like to leave a 15% tip. This means you'd like to leave 15% of $12.04. How much money should you leave total?

Click through the slideshow to learn how to calculate tips.

Let's say you went out to eat, and your bill is $12.04. You want to leave a 15% percent tip.
A tip is a percentage of the total. In this case, it means the tip is fifteen percent of $12.04.
Whenever you see the phrase "of something" in a math sentence, it's usually a hint that you'll need to multiply.
So we'll multiply 12.04 by 15%.
Before we can do that, we'll need to convert 15% into a decimal.
We'll move the decimal point two places to the left...
We'll move the decimal point two places to the left...so 15% becomes 0.15.
Now we can multiply. 0.15 times 12.04 equals 1.80.
So the tip is $1.80.
We could also say that 15% of $12.04 is $1.80.
Remember, a tip is extra money added to the total. So we'll add the tip to the bill.
1.80 plus 12.04 equals 13.84.
So the final price of the meal is $13.84, after including tip.
Let's try another example. Let's say you had excellent service and would like to leave a 20% tip for a meal that cost $68.80.
This means the tip will be 20% of $68.80.
We'll multiply 20% by 68.80.
First, we'll need to convert 20% into a decimal, so we'll move the decimal point two places to the left.
20% is the same as 0.20.
Now we'll multiply. 68.80 times 0.20 equals 13.76.
So the tip is $13.76.
Another way to say this is that 20% of $68.80 is $13.76.
Finally, we'll add the tip to the bill.
68.80 plus 13.76 equals 82.56.
The final price, after tip, is $82.56.