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- the time to travel from A->B = 3 hours
- Going from B->A has the same distance, but time of 3 and half hours
- you travel downhill at 75 mph
- over flat terrain at 60 mph
- and travel uphill at 50 mph
- the road is the same road each way
- So there are two different time functions..?
- lets use a simple example
- we have 10 mile walk. i can walk 5mph uphill and 7.5mph downhill.
- the walk is totally up or downhill.
- it would be 2 hours to walk up the hill
- but only 1 hour and 20 minutes down the hill
- We can probably model the difference between the two equations
- Let t1 and t2 represent times to walk uphill or downhill
- remember the speed = distance over time
- so time = distance over speed
- t1 = d/5, t2 = d/7.5
- if we know what t1 and t2 are, we can find out what d is
- and vice versa
- as distance = time multiplied by speed
- d = t1*5 = t2*7.5
- replace t1 and t2 with actual numbers
- d = 2*5 = 1*7.5 + 1/3*7.5
- d = 10 = 10
- :)
- now lets tackle the previous fight
- it takes 3 hours to travel from A to B
- but 3 and a half hours to travel back the same road
- going uphill averages 50 mph
- on flat terrain averages 60mph
- and going downhill averages 75 mph
- Let t1 represent A to B, t2 represent B to A
- time = distance over speed
- There will be 3 different distances, one for each terrain
- d1 : uphill, d2 : flat, d3 : downhill
- for t2, just flip down and up
- 3.0 = d1 / 50 + d2 / 60 + d3 / 75
- 3.5 = d1 / 75 + d2 / 60 + d3 / 50
- we can get d1 by multiplying both sides by its divisor
- 150.0 = d1 + 50d2/60 + 50d3/75
- subtract 50d2/60 + 50d3/75 from both sides
- d1 = 150.0 - 50d2/60 + 50d3/75
- Simplify terms
- d1 = 150.0 - 5d2/6 + 2d3/3
- we can do the same for the second distance
- 3.5 = d1 / 75 + d2 / 60 + d3 / 50 maybe?
- screw that
- im just going to start doing distance = time multiplied by speed
- let big D represent distance.. its made of smaller distances
- D = d1 + d2 + d3
- ...
- im stuck at how to make the equations
- i feel like this should work but idk what to do now
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