9514 1404 393
Answer:
2.50 dollars/cup
Step-by-step explanation:
The slope formula is helpful.
m = (y2 -y1)/(x2 -x1)
m = (57.50 -42.50)/(9 -3) = 15.00/6
m = 2.50 . . . . . dollars per cup
The slope of the line on the graph is 2.50 dollars per cup.
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Additional comment
Often, you are expected to ignore the units, so your answer would be 2.5.
The units come from the axis labels. The vertical axis has units of dollars, so the "rise" is 15 dollars between the marked points. The horizontal axis has units of number of cups, so the "run" between the marked points is 6 cups. When we find the slope as rise/run, the units come out dollars/cup--the amount added to the cash drawer for each cup sold.
