Question

How to find Average rate of change?

Answer 1

3,000 Cups of Coffee = $118

1,000 Cups of Coffee = $40

What is the Average rate of change between these numbers?

Answer 2

@phi

Answer 3

subtract cups of coffee
subtract dollars

then you can find change in coffee divided by change in dollars

Answer 4

3,000c - 1,000c = 2,000c

$118 - $40 = 78

So 2,000 / 78 = 25.6

So the average rate of change is approximately 25.6??

Answer 5

yes, but put in the units
25.6 cups per dollar

you could flip it and get
1/25.6 dollars per cup which is about
0.039 dollars per cup

Answer 6

Oh, so the average rate of change is $0.030 per cup?

Answer 7

is is $ 0.039 per cup (if you don't round)
which is closer to $0.04 per cup (not 0.03)

but I don't know which way they want it.

Answer 8

Okay well they have a table:

Cups Ordered | Price
0 | $7
500 | $25.50
1000 | $44
1500 | $62.50
2000 | $81
2500 | $99.50
3000 | $118

Answer 9

Um, can you explain why 0 cups ordered = $7 could mean?

Answer 10

First, if they give a table, it is normal to assume the first number is "x" and the second number is "y"

and we want the "slope" = change in y divided by change in x
so we want dollars per cup which is $0.039 / cup

the 0 cups $7.00 means they charged you to get into the club before buying anything. For example, a "cover charge"

Answer 11

Ohh I get it.

Answer 12

It says: Sketch a graph, labeling its key features, to show the price the coffee shop would pay Coffee Delivery A to have between 0 and 3,000 cups delivered each week.

Answer 13

yes, it will be a line . the slope is $ 0.039 per cup, and the y-intercept is $7

Answer 14

Oh, but how would I graph that?

Answer 15

I know how to put the y-intercept but how do I do the slope? Slope = (0.039,0)?