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Al and Ben are drivers for SD Trucking Company. One snowy day, Ben left SD at 8:00 a.m. heading east and Al left SD at 11:00 a.m. heading west. At a particular time later that day, the dispatcher retrieved data from SD’s vehicle tracking system. The data showed that, up to that time, Al had averaged 40 miles per hour and Ben had averaged 20 miles per hour. It also showed that Al and Ben had driven a combined total of 240 miles. At what time did the dispatcher retrieve data from the vehicle tracking system? A. 1:00 p.m. B. 2:00 p.m. C. 3:00 p.m. D. 5:00 p.m. E. 6:00 p.m.

Respuesta :

MathPhys

Answer:

B

Explanation:

Let's say Da is the distance Al drives and Db is the distance Ben drives.  And let's say that t is the amount of time that Al drives.

Using the distance equation, we can say:

Da = 40t

Db = 20(t + 3)

We know that Da + Db = 240, so:

240 = 40t + 20(t + 3)

240 = 40t + 20t + 60

180 = 60t

t = 3

So Al had been driving for 3 hours when the dispatcher retrieved the data.  Al started driving at 11 AM, so the dispatcher must have retrieved the data at 2 PM.

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