Question

(score for question 2: ___ of 4 points)

1. the average cost of a compact car at a certain dealership over the last 10 years has ranged from $14,000 to $18,500. suppose you were going to plot these points on a coordinate grid.

(a) what is a good scale to use for the y - axis? explain your reasoning.
(b) what is a good interval to use for the y - axis? explain your reasoning.
answer: i

Explanation:

(a)

Step1: Determine the range of values

The range of values is \(18500 - 14000=4500\).

Step2: Choose a scale

A good scale for the \(y -\)axis could be \(14000\) to \(19000\). This is because it covers the range from \(14000\) to \(18500\) and gives a bit of extra space above the maximum value for clarity.

(b)

Step1: Consider the range and ease of reading

Since the range is \(4500\) and we want an interval that divides the range into a reasonable number of parts.

Step2: Calculate the interval

An interval of \(500\) would be good. \(4500\div500 = 9\) intervals. Also, \(14000+500n\) (where \(n = 0,1,\cdots,9\)) gives values that are easy to read and plot. For example, \(14000,14500,\cdots,19000\).

Answer:

(a) A good scale for the \(y -\)axis is \(14000\) to \(19000\).
(b) A good interval for the \(y -\)axis is \(500\).