Question

using the graph, find the rate of change of a countrys defense outlays.
defense spending is decreasing by 17 billion (in current dollars) per year
(simplify your answer. type an integer or a simplified fraction. do not include the $ symbol in your answer.)

Explanation:

Step1: Identify two data points

Choose the first and last points: (1991, 320) and (1995, 220)

Step2: Calculate rate of change

Use slope formula: $\text{Rate of change} = \frac{\text{Change in spending}}{\text{Change in year}}$
$\text{Rate of change} = \frac{220 - 320}{1995 - 1991} = \frac{-100}{4} = -25$

Answer:

-25