# Lesson goal: Calculating a tip in a restaurant

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With the use of variables in mathematical expressions, you can program the computer to do useful calculations for yourself. How about the tip in a restaurant? If you know the cost of a meal $(meal)$, and decide what percentage to leave the server $(per)$, the tip will be $tip=per/100\times meal$. With this, the total cost of the meal will be $total=meal+tip$. See if you can finish the code below, and have a "tip calculator."

# Now you try. Try finishing this tip calculator based on the formulas discussed above.

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