Think about it this way. If we are putting 8 people into 2 cars, 4 in each car, then the number of ways is 8! / 4! 4! 2! (It doesn't matter which specific car you are sitting in, only matters who you are with). Start from there and you will get the answer. @rag25

amar and akbar run towards each other from opposite ends of a racing track and take 64s and 100s respectively to reach other end after crossing each other. amar and anthony also run towards each other from opposite ends of the same track and amar takes 96s to reach the other end after they cross ...

@chinki93 When two people run towards each other, starting simultaneously, at speeds a and b, if they meet after a time t, and take further time t1 and t2 to reach each other's starting points, then t1 / t2 = b^2 / a^2 and t = sqrt(t1 * t2). Try proving it. It is a simple and interesting proof, and will help strengthen your gut-feel in TSD.

Comparable results can be arrived at in Time and Work / Pipes and Cisterns as well.

sorry to piss off the QA Gods here but wanted to ask something ! in algebra manytimes we have to club a equation having power upto 4 into 2 identities for easy computation. can u please help me how to do that ?
eg for those who didnt understand what i wrote above
y^4-10y^3+5y^2+100y+100=0 int...