When you were born, both of your rich grandparents made a deal with your parents, to do with what money they'll give you for birthdays. Grandad's deal was :

I'll give you £1 for your first birthday. Then, the amounts that I give you each year will double every time

and Grandma said :

I will start by giving you £1 for your first birthday. Then, the amount I give you will be the combined total of all the last birthday presents that I have ever given you up to that point. Plus, every birthday you have that's a multiple of five, I'll give you an extra five pounds.

a)What amount of money do they each pay you for your 15th birthday

and

Who would have given you the most after 27 years?

assuming that I understood exactly the rules, and that I faithfully reproduced them on a spreadsheet:

a) On your 15th birthday,
Grandfather gives you: £16384
Grandmother gives you: £10832 + £5 = £10837

b) Grandfather gives you the most after 27 years:
he gives £134,217,727 (2^27-1)
grandmother gives £88,756,884 on the 27th birthday
Edited on September 30, 2003, 9:53 am

Posted by SilverKnight on 2003-09-30 09:50:57