Problem:
On Monday Taye has . Every day, he either gains or doubles the amount of money he had on the previous day. How many different dollar amounts could Taye have on Thursday, days later?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
We can systematically exhaust the cases using a tree diagram where the upper branch covers the case where the amount gains while the other branch represents the case where the amount doubles.
From the diagram, we can see that we end up with six unique dollar amounts after three days.
Thus, is the correct answer.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions