Chapter 8. Math and Finance

If I offered you $15,000 or one dollar that doubled every day for 30 days, which one would you choose? By the time we finish the chapter, you'll know if you've chosen wisely.

We'll use the Indian folktale by Demi, "One Grain of Rice," to inspire our project and to demonstrate the power of doubling. In the folktale, a village girl asks a greedy king to double a single grain of rice each day for thirty days as a way to accumulate enough rice to feed the hungry villagers.

In this chapter, we will illustrate the math behind the folktale and compare it to conventional interest-based accrual methods. Specifically, we will:

• Calculate the total amount of money if we double a dollar each day

• Collect user input via slider input controls

• Graph the results of a calculation using the pen and stamp tools

• Build interactive math problems using variables

• Calculate simple interest on an amount of money

I'm using dollars as the basis for my project, but the math works whether we use euros...