My graph

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If we were going 18 days the .01 doubled daily would be better to do because the intersecting point is less than the days so the penny's doubled daily would go up farther than the $100 daily.

The intersecting point of the graph is 17.41 which means that if there are only 17 days the better choice would be the $100 a day.

There are two scenarios:

1. You are paid $100 per day for 4 years

2. You are paid $.01 on the first day, then the amount paid doubles what you were paid on the previous day.