#### Jonathan897867

##### New member

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- Thread starter Jonathan897867
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That is almost all you need.

Rule #1 - If you don't know something, and you need to talk about it, give it a name!

Level Trip

F km = Trip DISTANCE on Flat Land -- This is what we need to answer the first question. Don't get distracted from this goal. Focus!

Distance = Rate * Time

F km = 50 km/h * Hmmm... We'll need another name!

T hr = Trip TIME on Flat Land

F km = 50 km/h * T hr

UpSlope Trip

Distance = Rate * Time

(50 km - F km) = 10 km/h * (2.2 hr - T hr)

Realization: IF you solve for the Average Rate, it had better be somewhere between 10 km/h and 50 km/h. 50 km / 2.2 hr = 22.72 km/h -- Nice.

- Joined
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So the problem becomes to solve the two equations, x+ y= 2.2 and 5x+ y= 5. There are many different ways to solve "two equations in two unknowns" but here the simplest, perhaps, is to solve for y, y= 2.2- x, and replace the "y" in the second equation with that: 5x+ 2.2- x= 4x+ 2.2= 5. 4x= 5- 2.2= 2.8. x= 2.8/4= 0.7. Since y= 2.2- x, y= 2.2- 0.7= 1.5.

Now, the