Brain Teasers
Planes Apart
Two planes fly once around the world together.
They both fly at a constant distance above the
surface of the Earth, one above the other.
On completion, one of the planes has travelled
two kilometres further than the other.
(Assume the Earth is a perfect sphere.)
How far apart (in metres) were the two planes?
They both fly at a constant distance above the
surface of the Earth, one above the other.
On completion, one of the planes has travelled
two kilometres further than the other.
(Assume the Earth is a perfect sphere.)
How far apart (in metres) were the two planes?
Answer
1000/pi [or 318.3 metres]Hide Answer Show Answer
What Next?
View a Similar Brain Teaser...
If you become a registered user you can vote on this brain teaser, keep track of which ones you have seen, and even make your own.
Solve a Puzzle
Comments
mad ade I firmly believe you like math, and that is a good thing.
If there's one bad airplane teaser, I haven't heard it!!
An explanation would have been good though - for the benefit of the non mathematical geniuses amongst us
The formula for circumference of a circle is C = 2*Pi*r. Apply a little bit of calculus and δC = 2*Pi*δr. 2000 = 2*Pi*δr. So the change in radius δr = 2000/2Pi = 318.3 m
A nice variation on an old teaser.
A nice variation on an old teaser.
To post a comment, please create an account and sign in.
Follow Braingle!