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Home > A2C > Chapter 4 > Lesson 4.1.2 > Problem 4-25

4-25.
  1. Lettie just got her driver's license. Her friends soon nicknamed her “Leadfoot” because she is always going 80 mph on the freeway even though the speed limit is 65 mph. Homework Help ✎

    1. At this speed, how long will it take her to travel 50 miles?

    2. How long would it take her if she drove the 50 miles at 65 mph?

    3. Speeding tickets carry fines of about $200 and usually increase the cost of insurance. If Lettie gets a ticket on this trip, then what would be her cost per minute of time saved?

Write an equation. Let x = # of hours Lettie drives, 80x = 50.

0.625 hours or about 37.5 minutes.

Write an equation similar to the one in part (a).

0.77 hours or about 46.2 minutes.

Divide $200 by the number of minutes saved.

At least $22.99 per minute.