Question 723996
On day 365, you will have saved $365. So the first term of this arithmetic sequence is 1, the last term is 365, and there are n = 365 terms


Now use the formula


Sn = n*(a1 + an)/2


S365 = 365*(a1 + a365)/2


S365 = 365*(1 + 365)/2


S365 = 66795


So you will have saved a total of $66795