66 lines
1.3 KiB
Markdown
66 lines
1.3 KiB
Markdown
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# transformers quiz answers
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Use functions to return values #LED #number #math #functions #return #docs
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This is the answer key for the [transformers quiz](/microbit/lessons/transformers/quiz).
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## 1. What is a 'function'?
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A function is a unit of code that performs a specific task and returns a result.
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## 2. Write the line of code to create a number variable called "x" is equal to 5.
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<br/>
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```
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let x = 5
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```
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## 3. Write the line of code to create a condition for 'on button pressed ("A")'
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<br/>
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```
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input.onButtonPressed("A", () => {
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})
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```
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## 4. Write the steps to create a function.
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<br/>
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Click on `script`, then `add new`, and select `function`.
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## 5. Create a function called double that will double whatever input parameter is passed into it.
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<br/>
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```
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export function double(n: number) : number {
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let r: number
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return n * 2
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return r
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}
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```
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## 6. Consider the following directions
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Call the `function` that doubles the variable **x**. (The `function` is going to return the doubled value after it is called). Assign the new value (10) to a variable which we will call `doubled`.
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<br/>
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```
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let doubled = double(x)
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```
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## 7. Refer to Question 6
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Write the code to call the function that doubles our new `variable` doubled. Assign the new value 20 to a variable we will call doubled twice.
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<br/>
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```
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let doubleTwice = double(doubled)
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```
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