Introduction to Distance-Rate-Time Applications
Example 1:
Jan drives south out of Denver and averages 65mph. How far is she from Denver after 3 hours.
Use the formula …
d r t
distance = rate × time
65 3 195
Jan drove 195 miles.
Introduction to Distance-Rate-Time Applications
Example 2:
Write an expression for the distance traveled if the average rate is r mph and the time is 6 hours.
Use the formula …
d r t
distance = rate × time
6r 6r
The distance is given by 6r.
A plane flies p mph in a wind that is 30 mph. Write expressions for the ground speed of the plane going:
1) With the wind
2) Against the wind
Introduction to Distance-Rate-Time Applications
Example 3:
1) Going with the wind, the planes ground speed is increased! The wind is helping the plane to fly at an increased rate.
ground rate = (rate of plane) + (rate of wind)
r p w
2) Going against the wind, the planes ground speed is decreased! The wind is causing the plane to fly at an slower rate.
ground rate = (rate of plane) - (rate of wind)
r p w