Jun 2, 2012

Shortest Distance from NewYork to Mumbai

Source: Discussions with BX Mumbai team on my flight from New York to Mumbai

Problem: The flight from New York (Newark - EWR) to Mumbai (Bombay - BOM) takes the aerial route as shown in the figure. Why do the flights not take straightline distance to minimize cost?

Hint: The answer is mathematical. Do not think of regulatory or political reasons.

Update: (19-07-2012) Assume earth is perfect sphere 

Jun 1, 2012

Permutations and Combinations Puzzle: Cube with Equal Faces

Source: Asked to me by Sumit Yadav

Is it possible to label the edges of a cube using the numbers 1 through 12, in such a way that the sums of the numbers on any two faces of the cube are equal?

Update: (19-07-2012)
Solution posted by Rakesh Roy (SAP Labs, Bangalore) and Praveen Reddy Vaka (Mechanical Engg IITM Alumnus 2006, CSE IIT Kanpur Alumnus 2011) in comments!

Fraction Brainteaser

Source: Sent to me by Gaurav Sinha Problem: Siddhant writes a Maths test and correctly answers 5 out of 6 Arithmetic questions and 20...