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Before we start, did you try solving the workbook yourself?

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If not, please click the link in the resources folder and follow the instructions for this workbook.

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Welcome to Work Book 4.2.

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We ate at a restaurant and our bill came to 53 bucks.

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And what we need to do is create a function that when called tips the waiter 15% of the bill.

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So what we'll do is we'll start with the familiar public static void void because you haven't learned

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about return values yet, so our function will not return anything.

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The function name is tip the waiter and the function takes in one parameter the bill.

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This parameter expects to receive a double value whenever this function gets called.

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And based on the bill value that gets provided, we need to calculate a tip.

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A tip is 15% of the bill, so we'll say double tip is equal to bill times 0.15.

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And then we print.

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Your service was wonderful.

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Please accept this tip.

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The tip being whatever we just calculated.

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And now we can call the function tip the waiter.

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And that's all we're calling the function, passing in a double that equals $53.

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The parameter is going to store the double value that gets passed in here we calculate a tip based on

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the value that was passed in and then we print it.

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Let us visualize the runtime using our trusty debugger.

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So here we're calling the function passing in a value of $53.

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Stepping inside the function, the parameter bill equals whatever value that was passed in $53 that

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times 0.15 results in a tip of 8.0 to 5.

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And here we're saying your service was wonderful.

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Please accept this tip.

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Person continue to resume runtime.

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And that is all.

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Let's say the bill was $75.

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This time we're passing in an argument of 75.

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I shouldn't have stepped over it.

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Let me restart.

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I'm going to step inside the function.

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The parameter bill stores the value that was passed in it equals 75, 75, 15% of that equals 11.25.

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Your service was wonderful.

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Please accept this tip of $11.

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Perfect.