ExampleGroupGroup4

Back to Example Group Problem

__Method__
Two columns in a spreadsheet. First column is 0-31. Second column is the amount of money received each day. Since it doubles each day we recognized it is exponential equation. So we plugged the formula y=2^(x-1) where y represents the amount of money earned and x represents the number of days passed. Using the table we can see how much money we made for any number of given days.

=(2^day)/100 ||
 * Day || Money in the bank
 * 1 || 0.01 ||
 * 2 || 0.02 ||
 * 3 || 0.04 ||
 * 4 || 0.08 ||
 * 5 || 0.16 ||
 * 6 || 0.32 ||
 * 7 || 0.64 ||
 * 8 || 1.28 ||
 * 9 || 2.56 ||
 * 10 || 5.12 ||
 * 11 || 10.24 ||
 * 12 || 20.48 ||
 * 13 || 40.96 ||
 * 14 || 81.92 ||
 * 15 || 163.84 ||
 * 16 || 327.68 ||
 * 17 || 655.36 ||
 * 18 || 1310.72 ||
 * 19 || 2621.44 ||
 * 20 || 5242.88 ||
 * 21 || 10485.76 ||
 * 22 || 20971.52 ||
 * 23 || 41943.04 ||
 * 24 || 83886.08 ||
 * 25 || 167772.16 ||
 * 26 || 335544.32 ||
 * 27 || 671088.64 ||
 * 28 || 1342177.28 ||
 * 29 || 2684354.56 ||
 * 30 || 5368709.12 ||
 * 31 || 10737418.24 ||

__Solution__
We would take the penny if the month had 31 days. Any other month we would take the 10 million dollars up front.

__Explanation__
Using the table in Excel we found that days 1-30 produced values less than 10 million dollars, however on day 31 the dollar value reached $10737418.24.