Elenore made an 850 mile trip east. She traveled 2 hours by jet and 30 minutes by a private propeller plane. If the speed of the jet was four times the speed of the propeller plane, what was the speed of the jet?

To find the speed of the jet, we can set up a system of equations based on the information given.

Let's assume the speed of the propeller plane is "x" miles per hour.

We know that Elenore traveled 2 hours by jet, so the distance covered by the jet is 2 times the speed of the jet.
Distance covered by the jet = 2 * speed of the jet

We also know that Elenore traveled 30 minutes (or 0.5 hours) by the propeller plane, so the distance covered by the propeller plane is 0.5 times the speed of the propeller plane.
Distance covered by the propeller plane = 0.5 * speed of the propeller plane

Given that the distance of the entire trip was 850 miles, we can write the equation:
Distance covered by the jet + Distance covered by the propeller plane = Total distance of the trip
2 * speed of the jet + 0.5 * speed of the propeller plane = 850 miles

Now, we are told that the speed of the jet is four times the speed of the propeller plane, so we can substitute 4x for the speed of the jet in the equation:
2 * (4x) + 0.5 * x = 850

Now we can solve the equation to find the value of x, which represents the speed of the propeller plane:

8x + 0.5x = 850
8.5x = 850
x = 100

Therefore, the speed of the propeller plane is 100 miles per hour.

To find the speed of the jet, which is four times the speed of the propeller plane, we can multiply 100 by 4:
Speed of the jet = 4 * 100 = 400 miles per hour.

Therefore, the speed of the jet is 400 miles per hour.

if the speed of the prop is x, then the jet is 4x.

Since distance = speed * time, we have

4x*2 + x * 1/2 = 850

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