Problema Solution
greg drove at a constant speed in a rainstorm for 282 miles. He took a break, and the rain stopped. He then drove 255 miles at a speed that was 4 miles per hour faster than his previous speed. If he drove for 11 hours, find the car's speed for each part of the trip
Answer provided by our tutors
Let
v = the speed of the car for the first part of the trip, v>0
v + 4 = the speed of the car for the second part of the trip
Since speed = distance/time follows time = distance/speed thus we have:
282/v + 255/(v + 4) = 11
........
........
v = 47 mph
v + 4 = 47 + 4 = 51 mph
The speed of the car for the first part of the trip was 47 mph.
The speed of the car for the second part of the trip was 51 mph.