I have a rope that goes around the equator of the earth. How much longer do I need to make the rope in order to raise the distance between the earth and the rope to 1m above the ground at all points?

Assume that the path around the equator is a perfect circle which has a radius of r meters. Then the length of the rope that goes around the equator is the circumference of this circle which is 2*pi*r meters.Your aim is to make the rope longer so as to achieve a radius of (r+1) meters. This requires a rope of length 2*pi*(r+1) meters. So you need to add a total of [2*pi*(r+1) - 2*pi*r] = 2*pi meters to the rope, or ~6.28 meters.

You don't actually need to lengthen the rope, depending on what rules you want to assume. You could just move it sideways by 3571.6 metres (although this does mean that you need to know the radius of the Earth and be able to do trigonometry in your head.)EC

easy, simple maths

I suspect the question is not designed to see if you can find the right answer, but whether you think in a logical and structured way. So it's not what the correct answer is (although that's nice to have), but your thought process for getting to it.

Sorry Mr. Client, the warehouse we've designed and built for you is three times bigger than you need, but look!, we thought through it in a logical and structured way. Also, we know you wanted it in Northampton but we thought about it laterally and you get the same solution if you move it East. What do you mean, Lowestoft's no where near your customers?

In addition, I can definitively tell you how many golf balls were sold in the USA in 2002 and how many miles of string there are in the world. What do you mean, you've been in this business for 35 years selling mattresses in Huddersfield and already know exactly who your potential customers are?

Thank you for your solution Mr MC - I'll sleep on it.

second poster:circumference = pi * r squared NOT 2 * pi * r

geek the fomula you have provided is to calculate the area, not the circumference. The post from answer is correct, circumference = pi*d = 2*pi*r.I guess you fail the interview!

Lowestoft - not a bad warehosue location to serve E Anglia what's the problem?

Wouldn't Norwich be better?

Norwich is now known as 'Aviva'.

Isn't Delia Smith a director of Aviva City FC?Geek - you suck bigtime at maths!!

Have you seen that fox who is the manager of Birmingham City FC?

Me? A fox? Why thank you, you dirty boy!

I darn't work at Bimmingham seedy footy club no more. I is taking a job wiv Alan Shugar for his apprentice show innit.