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24 votes
24 votes
Two jet planes simultaniously started traveling in opposite directions from the same airport. Four hours later, they where 3800 miles apart. Find the rate of each plane if one of them traveled 80 miles per hour faster than the other

User Hooch
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1 Answer

11 votes
11 votes

435 miles per hour, 515 miles per hour

Explanation:

Let us assume that plane A is traveling at 'x' miles per hour, then plane B is traveling at 'x+80' miles per hour. As the question says that one of them traveled 80 miles per hour faster than other.

After 4 hours they were 3800 miles apart.

We know that,


t = (distance)/(speed)

Since two planes are traveling in opposite directions, so we will add their speed.

Putting the values in the equation we get,


4 = (3800)/(x + (x + 80))

Now, solving for 'x'


4(x + (x + 80) = 3800


4x + 4x + 320 = 3800


8x = 3800 - 320


8x = 3480


x = (3480)/(8) = 435

So the rate of plane A is 435 miles per hour and the rate of plane B is (435+80 = 515) miles per hour.

User Puneet Singh
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