Finding the Average Rate of Change

A scuba diver is 30 feet below the surface 10 seconds after she entered the water, and 100 feet below the surface after 40 seconds. What is this scuba diver's rate of descent? Round to the nearest hundredth.

• 2.33 ft/sec

• 0.45 ft/sec

• 2.50 ft/sec

• 3.14 ft/sec

A rocket is one mile above the earth 30 seconds after launch and five miles above the earth 2.5 minutes after launch. What is the rocket's rate of change in miles per second?

• 0.03 mi/sec

• 1.80 mi/sec

• 0.23 mi/sec

• 0.15 mi/sec

A chef weighed 145 lbs in 1986 and weighed 190 lbs in 2007. What was this chef's rate of change in weight?

• 2.14 lbs/year

• 11 lbs/year

• 4.1 lbs/year

• 0.24 lbs/year

Michael started a savings account. 4 weeks after starting this account, he had $300 dollars in it, and after 9 weeks, he had $400. What was the rate of change of money in his savings account over this time?

• $20/week

• $140/week

• $50/week

• $7.69/week

After 30 baseball games, A-Rod had 25 hits. If after 100 games he had 80 hits, what is his average number of hits per game?

• 27 hits per game

• 0.79 hits per game

• 1.25 hits per game

• 0.83 hits per game

Which of the following is the correct equation to find rate of change?

• m=(y₂-y₁)/(x₂-x₁)

• m=(x₂-x₁)/(y₂-y₁)

• m=(y₂-x₂)/(y₁-x₁)

• m=(y₂+y₁)/(x₂+x₁)

A plane left Chicago at 8:00 AM central time. At 1:00 PM central time, the plane landed in Los Angeles, which is 1500 miles away. What was the average speed of the plane for the trip?

• 300 mph

• 214 mph

• 167 mph

• 620 mph

Every hour, a runner is able to run the same number of miles. After her 3rd hour of running she has gone 15 miles, and after her 5th hour of running she has gone 25 miles. What is the rate (speed) at which she runs?

• 5 mph

• 20 mph

• 0.2 mph

• 0.05 mph

True or False: "Slope" is just another word for rate of change. We tend to use this word when graphing the relationship between two quantities.

• True

• False

What was the average rate of change in the population from 1900 to 1990?

• 175 million people/year

• 1.94 million people/year

• 2.13 million people/year

• -1 million people/year