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JavaScript

Posted by Douglas Watts
Douglas Watts
5,464 Points

Help With This Numbers Challenge

Can someone please help me with this numbers challenge, i know nothing about math:

"Create a variable named "circumference" and assign the correct value to it by using the "diameter" variable and Math.PI. See the comment in the script for more information."

var diameter = 5.75,
          a = 17,
          b = 42,
          c = 1337,
          ageIfILiveToYear2100 = (new Date(2100, 0, 1) - new Date(1995, 5, 16, 7, 20)) / (1000 * 60 * 60 * 24 * 365.242);
      var circumference =

3 Answers

Jason Montoya
Jason Montoya
6,550 Points
Jason Montoya
Jason Montoya
6,550 Points

Doug,

If I remember right, to find the circumference of a circle when given the diameter you just multiply (pi * diameter).

PI is about equal to 3.14159 but instead of plugging that number in when using JavaScript, I think we just use Math.PI instead.

so something like this should hopefully work:

var circumference = Math.PI (5.75)

Hope this helps.

Michael Miller
Michael Miller
5,747 Points
Michael Miller
Michael Miller
5,747 Points

The formula for the circumference is:

Circumference = Pi * Diameter

or

var circumference = Math.PI * diameter

If only we could remember everything they taught us high school. :)

Douglas Watts
Douglas Watts
5,464 Points
Douglas Watts
Douglas Watts
5,464 Points

Thanks to both for great answers, that was correct!