Answer:you would have saved $31 after 5 days
Explanation:
You double the number of dollars in the envelopes from the day before. This means the amount in a day is double the amount in the previous day. Therefore, amount of money in the envelope is increasing in geometric progression. The formula for determining the sum of n terms of a geometric sequence is expressed as
Sn = a(r^n - 1)/r - 1
Where
a represents the first term.
r represents the common ratio.
From the information given,
a = 1
r = 2
n = 5 days
S5 = 1(2^5 - 1)/2 - 1
S5 = 32 - 1 = 31