Exercises: Data and Variables
Exercises appear regularly in the book. Just like the concept checks, these exercises will check your understanding of the topics in this chapter. They also provide good practice for the new skills.
We’ve included our solutions to some (but not all) of the exercises so that you can check your own work after you practice. As with any learning opportunity, take it seriously and give every exercise a fair shot before peeking at the solution. Our solution may not look exactly like yours, but that’s ok. There’s often more than one way to solve a problem with code.
You don’t need to show proof of completing the exercises to pass, so do them for your own benefit. And if they’re hard or you get some answers wrong on the first try, keep going! Your future self will thank you.
Unlike the concept checks, you will need a code editor to complete the exercises. We will be using Visual Studio Code
as our code editor.
Fork and Clone the following github repository to get started: JavaScript Projects
The Data
Use the information given below about your space shuttle to complete the exercises:
Data | Value |
---|---|
Name of the space shuttle | Determination |
Shuttle Speed (mph) | 17,500 |
Distance to Mars (km) | 225,000,000 |
Distance to the Moon (km) | 384,400 |
Miles per kilometer | 0.621 |
The Exercises
Declare and assign variables
- Declare and assign a variable for each item in the Data Table above.
When declaring and assigning your variables, remember that you will need to use that variable throughout the rest of the exercises. Make sure that you are using the correct data type!
Print out the type of each variable
For each variable you declared in part A, use the
typeof
operator to print its type to the console, one item per line.Verify your code works as expected by running the program. Once you have the correct output move on to Calculate a space mission!
In order to run your program, open a terminal and navigate to the directory containing your data-and-variables-exercises.js
file.
The following command will run any code within the file:
node data-and-variables-exercises.js
Calculate a space mission!
We need to determine how many days it will take to reach Mars.
Create and assign a miles to Mars variable. You can get the miles to Mars by multiplying the distance to Mars in kilometers by the miles per kilometer.
Next, we need a variable to hold the hours it would take to get to Mars. To get the hours, you need to divide the miles to Mars by the shuttle’s speed.
Finally, declare a variable and assign it the value of days to Mars. In order to get the days it will take to reach Mars, you need to divide the hours it will take to reach Mars by 24.
Print out the results of your calculations
Using variables from above, print to the screen a sentence that says
"_____ will take ___ days to reach Mars."
Fill in the blanks with the shuttle name and the calculated time.Verify that your code works as expected by running the program. Once you have the correct output move on to Calculate a trip to the Moon
Calculate a trip to the Moon
Repeat the calculations, but this time determine the number of days it would take to travel to the Moon and print to the screen a sentence that says "_____ will take ___ days to reach the Moon."
.