Concepts of Biology (BIOL116) - Dr. S.G. Saupe; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321; ssaupe@csbsju.edu; http://www.employees.csbsju.edu/ssaupe/

Persian Courtier Story

There is an old Persian legend that a courtier presented a beautiful chessboard to his king.  The king was so grateful that he asked what he could give him in return.  The courtier requested that the king give him 1 grain of rice for the first square on the board, double the amount to two grains for the second square, double it again to 4 grains for the third and so on.  The king readily agreed and ordered rice to be brought from the royal storeroom.  How many grains would the King have give for the first 15 squares?  The first 10 and done for you.

 Square Number Grains of Rice Log of grains of rice 1 1 0 2 2 0.3 3 4 0.6 4 8 0.9 5 16 1.20 6 32 1.51 7 64 1.81 8 128 2.10 9 256 2.41 10 512 2.71 11 12 13 14 15

Exercises:

1. Complete the table.
2. Plot grains of rice vs. square number.  Plot log of grains vs. square number on the same graph.  What do you conclude from these graphs?