# The cost of a first-class postage stamp in 1962 was 4. In 1999 it is 33. The cost was (and is) growing exponentially. What was the growth rate?

##### 1 Answer

Jul 25, 2018

**The growth rate was**

#### Explanation:

Time interval is

Initial cost in

Final cost in

Exponential growth function :

is rate of growth in decimal form.

sides we get,

The growth rate was