A worker is paid $0.05 on the first day, $0.10 on the second day, $0.20 on the third day, $0.40 on the fourth day, and so on. How much money (rounded to the nearest cent) in total does the worker earn after working 21 days?
this is a geometric sequence with a common ratio of 2
an = a1 * r^(n - 1) n = term to find = 21 a1 = first term = 0.05 r = common ratio = 2 now we sub a21 = 0.05 * 2^(21 - 1) a21 = 0.05 * 2^20 a21 = 0.05 * 1048576 a21 = 52428.80 <==== after working 21 days
