(Hint: the expected yearly $/£-rate is defined as the average $/£-daily
rate is: 1/n . sum 1 to n of Xi for i = 1,...n=365 .The expected yearly £/$-rate is 1/n sum 1 to n of 1/Xi
WHERE Xi is the $/£-Rate on the ith day.
My first impression is that obviously the expected rate should be the inverse which = 2/3. Im having trouble proving it though:
1/365 ( X1 + X2 + ... + X365) = 3/2
1/365 (1/X1 + 1/X2 + ... + 1/X365) = y
Can equate them by setting 1/365 = 3/2 . 1/(X1 + X2 + ... + X365) = y/(1/X1 + 1/X2 + ... + 1/X365)
But I just can not get anywhere! Any help welcome!