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In the last exercise, we pointed out that using `return` makes programs more maintainable and flexible, but how exactly?

When functions `return` their value, we can use them together and inside one another. If our calculator needed to have a Celsius to Fahrenheit operation, we could write it with two functions like so:

``````function multiplyByNineFifths(celsius) {
return celsius * (9/5);
}

function getFahrenheit(celsius) {
return multiplyByNineFifths(celsius) + 32;
}

console.log('The temperature is ' + getFahrenheit(15) + '°F');
// Output: The temperature is 59°F
``````

Take a look at the `getFahrenheit` function. Inside of its block, we called `multiplyByNineFifths` and passed it the degrees in `celsius`. The `multiplyByNineFifths` function multiplied the `celsius` by `(9/5)`. Then it returned its value so the `getFahrenheit` function could continue on to add `32` to it.

Finally, on the last line, we interpolated the function call within a `console.log` statement. This works because `getFahrenheit` returns it's value.

We can use functions to section off small bits of logic or tasks, then use them when we need to. Writing functions can help take large and difficult problems and break them into small and manageable problems.

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