# Interactive video lesson plan for: Calculating a 15 percent tip without a calculator

#### Activity overview:

Learn how to calculate a 15 percent tip in your head. This simple technique makes calculating a 15 percent so easy you can do it in your head .

Hello welcome to MooMooMath. were we upload a new math video everyday
In this video I would like to show how to calculate a 15 percent tip if you are out and need to tip.
First we have ten dollars, and we would like ti tip 15 percent.
Step one is to figure out what a 10 percent tip would be.
You can just move the decimal one place to the left,and this becomes 1
Next I figure what a 5 percent would be by taking half of the 10 percent tip.
One half of a dollar is 50 cents so the tip would be 1.50 for ten dollars.
Next we have 30 and I will take ten percent of 30 dollars by moving the decimal to the left.
Next I take one half of 3 which is 1.50.
Add these together and you get 4.50
When you eat out you usually don't get exact numbers.
What if you get a number like 23.78
What I will do is round the number up to 24 and repeat the same process.
Move the decimal one place to the left which becomes 2.40
Next take one half of that which is 1.20 so I will tip 3.60
I'll complete a couple more of these.
41.67
I will round to 42.
Move the decimal to the left and I get 4.20.
Take one half of this to get 2.10.
Add these together and I will tip 6.30
Next I have 67.87.
Round to 68
Move the decimal one to the right.
Take one half of this which is 3.40
Add these numbers together and I get 10.20
Finally I have 5.63
I will round to 6
Move the decimal to the left.
Take one half of this.
This gives me ..60 plus .30 which equals 90 cents.
Thanks for watching. MooMooMath uploads a new math video everyday

Keywords : Percents | Percentage | tip | tipping | Calculating a tip |

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Tagged under: percent,tip,percentages easy,math,tipping waiters lot money,tip calculator

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