What is the formula for an eastbound car is going 4 miles per hour faster than a westbound car. the cars are 208 miles apart 2 h
ours after passing each other on a highway. what is the speed, in miles per hour, of the eastbound car?
1 answer:
Draw a diagram to illustrate the problem as shown below.
Let v = speed of the westbound car, mph
Because the eastbound car travels 4 mph faster than the westbound car, its speed is (v+4) mph.
After 2 hours,
the westbound car travels 2v miles west, and the eastbound car travels 2(v+4) miles east.
Because they become separated by 208 miles, therefore
2v + 2(v+4) = 208
4v + 8 = 208
4v = 200
v = 50 mph
The westbound car travels at 50 mph.
The eastbound car travels at v+4 = 54 mph
Answer: The eastbound car travels at 54 mph.
Let v = speed of the westbound car, mph
Because the eastbound car travels 4 mph faster than the westbound car, its speed is (v+4) mph.
After 2 hours,
the westbound car travels 2v miles west, and the eastbound car travels 2(v+4) miles east.
Because they become separated by 208 miles, therefore
2v + 2(v+4) = 208
4v + 8 = 208
4v = 200
v = 50 mph
The westbound car travels at 50 mph.
The eastbound car travels at v+4 = 54 mph
Answer: The eastbound car travels at 54 mph.
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