Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trial
Alexander Foster
4,725 PointsUsing exponential notation, create a variable named "GermanyGDP" and assign the number 3.4 trillion (3400000000000) to it.
Anyone else typing the right answer in and having the code editor tell you to use "Exponential notation?" I typed in var GermanyGDP = 3.4E12 which is 3400000000000 like it is asking for but it is saying i am not using exponential notation...which clearly i am.... I also tried 34E11 whih is also 34 trillion but that doesnt work either... Is it a bug or am i missing something? It works in my my javascript console..sooo ooo
7 Answers
Ben Rubin
Courses Plus Student 14,658 PointsNumbers that begin with 0x are actually hexadecimal numbers (base 16). Using hexadecimal, 0x10 is equal to 16, but that's because hexadecimal numbers are base 16. Octal numbers are base 8.
In decimal notation (our regular everyday base 10 number system), the rightmost digit is the"ones" digit, the digit to the left of that is the "tens" digit, the digit to the left of that is the "hundreds" digit and so on. Notice that each digit ("ones", "tens", "hundreds", "thousands", and so on) is ten times more than the digit to its right (which is why it's a base 10 number system).
So following the same pattern with octal (base 8) notation, each digit place is eight times more than the digit place to its right because the number system is base 8. Hopefully this example makes it a little more clear.
In a decimal (everyday base 10 system), the number 1234 can be looked at like this:
1234 = (1 * 1000) + (2 * 100) + (3 * 10) + (4 * 1)
Taking the number 1234 into octal (base 8) it would be
01234 = (1 * 512) + (2 * 64) + (3 * 8) + (4 * 1) = 668 in decimal
The reason the question is saying to add 2 to the octal number 016 is because 016 equals 14 in decimal ((1 * 8) + (6 * 1)). So you need to add 2 to it to get 16 decimal. However, keep in mind that in octal notation, there is no single digit for the number 8, just as in decimal notation there is no single digit for the number 10.
For instance, in decimal if you add 18 + 2, you get 20. So in octal notation, if you add 016 + 02 you get...
Ben Rubin
Courses Plus Student 14,658 PointsI copied that line of code directly from your post and it worked for the quiz. It looks like you did everything correctly. I don't know why it's not passing. Here's the complete code I'm using, which is passing the quiz.
<!DOCTYPE html>
<html lang="en">
<head>
<title> JavaScript Foundations: Creating Numbers</title>
<link rel="stylesheet" href="core.css">
<script>
// exponential notation
// 1E6 === 1000000
// 1.23E6 === 1230000
// octal number literals
// 06 === 6
// 07 === 7
// 010 === 8
// 011 === 9
// 012 === 10
var GermanyGDP = 3.4E12
</script>
</head>
<body>
<h1>JavaScript Foundations</h1>
<h2>Creating Numbers: Part 2</h2>
<script src="viewer.js"></script>
</body>
</html>
Ben Rubin
Courses Plus Student 14,658 PointsI posted my code to demonstrate that I copied Alexander's code exactly as he posted it and it passed the quiz. I didn't give him anything that he didn't already do.
James Barnett
39,199 PointsYou forgot your semicolon at the end of your line of JavaScript.
Juliano Vargas
Courses Plus Student 15,575 Pointsplease anyone can help me with this question : Create a variable named "mevol" and assign the value 16 to it using an octal number literal. this i what i tried 010 it says to add 2 to your octal literal 016. i am not sure where to add it I know this 0x10 will give me 16 but will give for the task anyone ?
Juliano Vargas
Courses Plus Student 15,575 Pointshumm so the answer will be 020 i get it thank's for that
Alexander Foster
4,725 PointsThanks for the help guys, My problem was that i didnt put the script in the right tag.....Haha just a case of not paying attention. Love how quick this form is to help those in need! thanks guys
Iain Campbell
4,009 PointsI found this Youtube tutorial useful in understanding octal numbering et al!