a 360 mile trip began on a greeway in a car traveling at 62 mph. Once the road became a 2 lane highway, the car slowed to 54 mph. If the tot

Question

a 360 mile trip began on a greeway in a car traveling at 62 mph. Once the road became a 2 lane highway, the car slowed to 54 mph. If the total trip took 6 hours, find the time spent on each type of road

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Kiệt Gia 1 year 2021-09-02T21:17:13+00:00 1 Answers 0 views 0

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    2021-09-02T21:19:12+00:00

    Answer:

    Time spent on the greenway road  = 4.5 hours

    Time spent on the 2 lane road = 1.5 hours

    Explanation:

    The distance of the trip  is 360 miles and the initial speed of the car is 62 miles/hr and after the road became 2 lane highway the car slowed to 54 miles/hr.

    Let us divide the trip into two

    Greenway

    speed = distance/time

    speed = 62 mph

    time = a

    distance = speed × time

    distance = 62a

    2 lane highway

    speed = distance/time

    speed = 54 mph

    time = b

    distance = speed × time

    distance = 54b

    Total distance

    62a + 54b = 360………………….(i)

    Total time

    a + b = 6…………………………(ii)

    a = 6-b

    insert a in equation (i)

    62(6-b) + 54b = 360

    372  – 62b + 54b = 360

    -8b = 360-372

    -8b = – 12

    b = 12/8

    b = 1.5

    from equation (ii)

    a + 1.5 = 6

    a = 6 – 1.5

    a = 4.5

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