### Home > CCA2 > Chapter 2 > Lesson 2.1.4 > Problem2-63

2-63.

Below are two situations that can be described using exponential functions. They represent a small sampling of the situations where quantities grow or decay by a constant percentage over equal periods of time. For each situation: Homework Help ✎

• Find an appropriate unit of time (such as days, weeks, years).

• Find the multiplier that should be used.

• Identify the initial value.

• Write an exponential equation in the form $f(x)=ab^x$ that represents the growth or decay.

1. A house purchased for \$120,000 has an annual appreciation of 6%.

Years; 1.06; 120,000

$f(x)=120000(1.06)^{x}$

2. The number of bacteria present in a colony is 180 at noon, and it increases at a rate of 22% per hour.

This problem is similar to part (a) above.