Ajetliner is traveling east from salt lake city to washington dc, a distance of 1,850 miles. the jetliner travels at an average air speed of 590 mph relative to the air. at the jetliner's altitude, the wind is blowing 36 mph to the west. how long does the journey take?

21.

Remark

The jet liner is flying against the wind. Therefore the speed of the wind is subtracted from the speed of the aircraft.

Givens

Net Speed = 590 - 36

Net Speed = 554

d = 1850

t = ??

Formula

d = r * t

t = d / r

t = 1850/554

t = 3.34 hours

22

Remark

The person going up is going at + 10. The person going down appears to be going 12.5. The person going up cannot tell what he is doing (or that's what you assume). All he knows for sure is that the second balloon appears to be going down at a rate of 12.5.

In reality, the person on the ground sees what is really happening. His formula is up - appearance to A = down

10 - appearance to A = down

10 - 12.5 = down

- 2.5 = down

23.

You are helped in this question if you understand that B is eventually going to pass A. It won't happen immediately, but it will happen. This question is so much easier if you drive a car. The speed as seen on the ground is the difference between the two balloons. Balloon A is running away from B, just not fast enough.

The ground observer sees what is actually happening. The net velocity is

7.5 - 5.0 = 2.5 if up is the positive direction.

24

This one is actually the worst one of the lot. She thinks she sees the car on her left moving forward. She has no idea what is really happening until she looks to her right.

If you have ever been on a train, you know how tricky this can be. Is the car to her left moving at all? The question does not clarify this unfortunately. Assume it is not. Then it is she that is moving backward.

The answer then is D

757764

step-by-step explanation:

de77737dd

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.