Calculating Interest Rates (Example)

How do you determine the annual interest rate?

Present Values         Future Values           Time Period
_____________________________________________________

100                            115.76                          3-years

200                            262.16                          4-years

100                            110.41                         5-years

Coca-Cola (Example)

In 1995 coca-cola enterprisees neede to borrow about a quater of a billion dollars for 25-years. It did so by selling IOUs, each of which simply promised to pay the holder $1,000 at the end of 25-years. The market interest at the time was 8.53-percent. How much would you have been prepared to pay for one of the company's IOUs? 

PV=$1,000 X  ___1_____
                      (1.0853)25

Can you please explain this equation step by step? Also, were does the 25 fit in at??