Algebra

posted by Kevin

Barbara and her husband take a trip on a highway, a distance of 600 miles. They intend to average 60 m.p.h. and take 10 hours. However, they take 11 hours due to construction. When they encounter the construction, they reduce their speed to 40 m.p.h. and proceed at this speed until they reach their destination. How many miles from their starting point did they come to the construction?

  1. Reiny

    distance at 60 mph --- x
    distance at 40 mph --- 600-x

    time at 60 mph = x/60
    time at 40 = (600-x)/40

    x/60 + (600-x/40 = 11
    times 120

    2x + 3(600-x) = 1320
    2x+1800 - 2x = 1320
    -x = -480
    x=480

    The encountered the construction after going 480 miles

    check:
    480/60 + 120/40 = 8 + 3 = 11

Respond to this Question

First Name

Your Answer

Similar Questions

  1. math

    your family is driving to houston,texas.A sign indicates that you are 700 miles from houston.Your car's trip odometer indicates you are 400 miles from home.YOu are traveling at an average speed of 60 miles per hour. A. write an expression …
  2. pre-algebra

    your family is driving to houston,texas.A sign indicates that you are 700 miles from houston.Your car's trip odometer indicates you are 400 miles from home.YOu are traveling at an average speed of 60 miles per hour. A. write an expression …
  3. math

    Hannah took a trip yo visit her cousin. She drove 120 miles to reach her cousin's house and the same distance back home. a) It took her 1.2 hours to get halfway to her cousin's house. What was her average speed, in miles per hour, …
  4. Algebra

    Beth is a bush pilot in Alaska. On a recent trip, she flew 600 miles with a tail wind in four hours. On the return trip, it took five hours to fly the 600 miles against the wind. Find the speed of the plane with no wind. Could you …
  5. Algebra 2

    A bicycle builder makes two models. The basic model requires 2 hours of frame construction, 4 hours of assembly, and 1 hour of finishing. The deluxe model requires 3 hours of frame construction, 3 hours of assembly, and 2 hours of …
  6. Algebra 2 (Linear Programming)

    A bicycle builder makes two models. The basic model requires 2 hours of frame construction, 4 hours of assembly, and 1 hour of finishing. The deluxe model requires 3 hours of frame construction, 3 hours of assembly, and 2 hours of …
  7. physics

    You leave your home at noon hoping to get to your destination, which is 300 miles away, by 5 p.m. During the first two hours of your trip you encounter road construction and only average 40 mph. What average speed do you need to maintain …
  8. physics

    You leave your home at noon hoping to get to your destination, which is 300 miles away, by 5 p.m. During the first two hours of your trip you encounter road construction and only average 40 mph. What average speed do you need to maintain …
  9. Algebra

    Norman traveled 261 miles on a trip to bates. The trip took 4 1/2 hours. If he then drives for 1 1/2 hours to leighsville, which is another 81 miles farther, what its his average rate of travel for the entire trip?
  10. Algebra 2

    You and a friend take turns driving on a 450 mile trip. Your friend drives for 3.5 hours at an average speed of 60 miles per hours. What must your average speed be for the remainder of the trip if you want to reach your hotel in 4 …

More Similar Questions