Problema Solution

A bus travels 15mph, another bus travels 75mph opposite direction, both leave station at 10:00am. What time will they be 780miles apart.?

Answer provided by our tutors

Let

v1 = 15 mph the speed of the first bus

v2 = 75 mph the speed of the second bus

d = 780 mi the sum of the distances that each bus passes

t = the time of the travel

Using the formula distance = time*speed we have:

v1t + v2t = d

15t + 75t = 780

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click here to see the equation solved for t

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t = 26/3 hr

t = 8 hr 2*60/3 min

t = 8 hr 40 min

8 hours and 40 min after 10:00 am is 6:40 pm.

At 6:40 pm the buses are 780 miles apart.