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Need help with a "Measuring the earth" Question (1 Viewer)

Enchantress91

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Can someone please help me out with this question?

The distance between Capetown (34 deg S, 17 deg E) and Sydney (34 deg S, 151 deg E) is 12500km.

Show that the radius of the parallel of latitude on which Sydney and Capetown both lie is 5300km (correct to 2 sigfigs). (2 marks)

I'm really struggling with Gen Math! I used enjoy it coz it was soo easy but now I'm dying!!!
 

Kat92

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So what we do is:

Longitude difference= 151 degrees- 17 degrees =134 degrees.

Fraction of circle= 134/ 360 = 67/180

Arc length= 12500=67/180*2*pi*r

Combine like terms and use the properities of equality to get the variable on one side of the equals sign and the numbers on the other. Remember to follow the order of operations.

67pi/90 r= 12500

Divide both sides of the equation by 67pi/90

r=1125000/67pi

r=1125000/67pi
=approx 5344.76
 

Kat92

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Your welcome, glad to help. It is also good revision practice.
 

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