Question

alicia bought a notebook and several erasers at the student store. the graph shows the relationship between the total cost of her items and the number of erasers she purchased. what is the cost of each eraser? $1.00 $1.50 $2.00 $3.50 purchase at student store total cost ($) 10 9 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 9 number of erasers

Explanation:

Step1: Identify two points on the line

Let's take the points (0, 2) and (2, 5). When the number of erasers (x - axis) is 0, the total cost is $2. This is the cost of the notebook.

Step2: Use slope - formula for cost per eraser

The slope formula is $m=\frac{y_2 - y_1}{x_2 - x_1}$. Here, $(x_1,y_1)=(0,2)$ and $(x_2,y_2)=(2,5)$. So $m=\frac{5 - 2}{2-0}=\frac{3}{2}=1.5$. The slope represents the cost of each eraser.

Answer:

$1.50