Chapter 3 Section 4

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Chapter 3 Section 4

• Rates of Change

2
Warm Up Quiz

• Graph y 2x 2 by hand (UGP) by plotting at
  least 3 points.
• Using your calculator, give a sketch of the graph
  of y x3 2
• Find the intercepts of 2x 3y 18 and use
  those to produce the graph (UGP)

3
Rate

• A rate is a ratio that indicates how two
  quantities change with respect to each other. For
  example, if you walked 20 meters (m) in 5 seconds
  (s), your rate would be

4
More Examples

• Fortuna has been growing each year. If 3200
  residents have moved in during the last 5 years,
  then the growth rate could be stated as
  3200res/5years or 640 resident per year.
• If you drive 27 miles in 30 minutes you averaged
  27mile/0.5hours or 54 mph.

5
Visualizing Rates

• The following graph shows data from an MCI phone
  call (land line) from San Francisco to Pittsburg,
  PA. At what rate was the customer being billed?

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Visualizing Rates
7
Car Rental

• Sarah rented a van to take the CR disk golf team
  to Crescent City for a match. The vehicle had a
  full tank and 13,741 miles on the odometer when
  she picked it up on March 1. On March 4, she
  returned the van with 14,014 miles on the
  odometer and used 13 gallons of fuel. Sarah paid
  118 total for the rental.
• What was the vans rate of gas consumption in
  miles per gallon?
• What was the average cost of the rental in
  dollars per day?
• What was the rate of travel in miles per day?
• What was the rental rate in cents per mile?

8
Fires

• In 2001, there were approximately 1.7 million
  fires in the United States and the figure was
  dropping at a rate of about 0.1 million per year.
  Draw a graph that represents this information. Be
  sure and scale and label the axes appropriately.

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NASA Spending
At what rate is the spendingat NASA changing?
14.5
14.4
Amount Spent in Billions
14.3
14.2
14.1
14.0
1997
1998
1999
Year