SOLUTION: If the latitude of Chicago is about 42 degrees and the radius of the earth is about 4000 miles, how far is Chicago from the equator? ( use pi= 3.1416)

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Question 207286: If the latitude of Chicago is about 42 degrees and the radius of the earth is about 4000 miles, how far is Chicago from the equator? ( use pi= 3.1416)
Found 2 solutions by HyperBrain, ikleyn:
Answer by HyperBrain(694) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=distance of Chicago from the equator.
---
x=r sin A=(4000 mi)(sin 42)=2677 mi

Answer by ikleyn(53937) About Me  (Show Source):
You can put this solution on YOUR website!
.
If the latitude of Chicago is about 42 degrees and the radius of the earth is about 4000 miles,
how far is Chicago from the equator? ( use pi= 3.1416)
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        The solution and the answer in the post by @HyperBrain are incorrect.
        His method is wrong, his formula is irrelevant.

        See my correct solution below. 


In this problem, the distance from the equator to Chicago is the length of the arc of 42 degrees
on a circle of the radius 4000 miles.


So, apply the standard formula for the arc length via the radius and the central angle

    arc length = 2%2Api%2A%2842%2F360%29%2A4000 = 2%2A3.1416%2A%2842%2F360%29%2A4000 = 2932.16 miles.


ANSWER.  The distance from Chicago to equator is about 2932 miles.

Solved correctly.