Thursday, 7 April 2011

Fulbright Commission (2)

As posted earlier, I've spent the day down at the Fulbright Commission library to read up on various schools, to see what a good reference letter is supposed to look like (to give pointers to my referees) and to run through a number of practice questions from the vast collection of prep books they have over there :)

The number of silly mistakes being made on the quant section is still worrying me, mistakes that I hope not to repeat next week as the exam isn't the cheapest one I've sat.....  time will tell and there are still two practice tests to get through.

Also met two nice folk who were planning to take their undergraduate degrees in the US - one of them had been wait-listed for Harvard and both were looking seriously at the funding options available to them.  It's pretty amazing that despite the high headline figures often quoted for the top universities there are so many opportunities for having the course funded without knocking on the local bank manager's door (and probably being charged for the honour of doing so).

I saw a neat trick of simplification the other day - a combination question where you knew how many you choose (2) and you knew the number of combinations (15), just not the overall sample size

starting with: nC2 = 15

n! / 2! (n-2)! = 15    <<< the formula for nCr where r=2 and we know the result = 15

n * (n-1) * (n-2)!  /   2! (n-2)! = 15  <<< as n! = n*(n-1)*(n-2)*(n-3)....*(n-n)  or simply n*(n-1)*(n-2)!

(n^2 - n) / 2 = 15  <<< as we have (n-2)! on top and bottom, we can eliminate to leave n(n-1), which multiplies out to n squared minus n

n^2 - n = 30

n = 6

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