Calculating a problem when unsure of variable - please help

roseclose3000

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Ok so my math teacher absolutely sucks at explaining anything and jumps over so many things when showing the class how to do new types of problems. I'm having a really hard time with one of the word problems from the homework. Can someone please help me figure out how to solve it?

Q: A chartered sight-seeing flight over the grand canyon is scheduled to return to its departure point in 3 hours. If the plane flies at 100 mph in still air and there is a head wind of 20mph on the outward journey, how far can the plane go before it must turn around?
A: ?

I'm not even sure what I'm supposed to be solving for here?
 
Can someone please help me figure out how to solve it?
To learn the basics of setting up this sort of exercise, try here and then here.

Q: A chartered sight-seeing flight over the grand canyon is scheduled to return to its departure point in 3 hours. If the plane flies at 100 mph in still air and there is a head wind of 20mph on the outward journey, how far can the plane go before it must turn around?
A: ?

I'm not even sure what I'm supposed to be solving for here?
They ask for a distance, so you should probably be trying to find a "distance" value.

Using the set-up methodology described at the links, you have the plane's speedometer reading (the "in still air" speed) of "p", 100, and the wind's rate of "w", 20. Then:

. . .outbound:
. . . . .rate: p - w = 100 - 20 = 80
. . . . .time: t
. . . . .distance: d = rt = [fill this in]

. . .inbound:
. . . . .rate: [fill this in]
. . . . .time: 3 - t
. . . . .distance: d = rt = [fill this in]

Since the distances there and back must be the same, set the two "distance" expressions equal, and solve for the remaining variable, being the time "t" for the outbound trip.

If you get stuck, please reply showing your steps, starting from your completion of the table above. Thank you! ;)
 
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