Just a little confused.

[Vampchick31]

Find the average rate of change in y relative to x for the ordered pairs. Include units of measure in your answer.

(2,12); (5,30) x is measured in hours and y is measured in dollars

(0,11); (3,50) x is measured in gallons and y is measured in miles

(3,10); (5,18) x is measured in seconds and y is measured in feet


:?: I'm not sure how to set up the problems. :? Please help.

~NikkiT~

 

[wjm11]

Find the average rate of change in y relative to x for the ordered pairs. Include units of measure in your answer.

(2,12); (5,30) x is measured in hours and y is measured in dollars

(0,11); (3,50) x is measured in gallons and y is measured in miles

(3,10); (5,18) x is measured in seconds and y is measured in feet

The “average rate of change” is just the slope. It might help if you plot the points on an xy graph. Remember, slope is just the change in y divided by the change in x. Consider the first two points, (2,12); (5,30). The change in y is

30 – 12 = 18

The change in x is

5 – 2 = 3

The slope/average rate of change is

(30 – 12)/(5 – 2) = 18/3 = 6

The units for y are $$$, and for x it’s hours, so the answer is $6/hr.