Posted by chelsea on Monday, October 22, 2012 at 3:55am.
how much money would you have after 20 weeks if you were given 5c the first week, 10c the second, 20c the third, 40c the fourth, and so on?

MATHS  Reiny, Monday, October 22, 2012 at 9:11am
looks like a geometric series
5 + 10 + 20 + 40 + ... for 20 terms
a = 5 , r = 2
Sum(2) = 5(2^20  1)/(21) = 5242875 c