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A small jet can fly 2040 miles in 4 hours with a tailwind but only 1560 miles into a headwind. Find the speed of the jet in still air and the speed of the wind

User Cui Heng
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Answer:

Let's call the speed of the jet in still air "j" and the speed of the wind "w".

When flying with the tailwind, the effective speed of the jet is j + w. We know that it can travel 2040 miles in 4 hours, so:

2040 = 4(j + w)

Simplifying this equation, we get:

j + w = 510

When flying into the headwind, the effective speed of the jet is j - w. We know that it can only travel 1560 miles in 4 hours, so:

1560 = 4(j - w)

Simplifying this equation, we get:

j - w = 390

Now we have two equations with two variables:

j + w = 510

j - w = 390

We can solve this system of equations using elimination. Adding the two equations, we get:

2j = 900

Dividing both sides by 2, we get:

j = 450

So the speed of the jet in still air is 450 mph.

Now we can use either equation to solve for the speed of the wind. Let's use the first equation:

j + w = 510

Substituting j = 450, we get:

450 + w = 510

Subtracting 450 from both sides, we get:

w = 60

So the speed of the wind is 60 mph.

Explanation:

User Morteza Malvandi
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