Question 529388
A hiker traveled at an average rate of 2 kilometers per hour (km/h) going up to a lookout and traveled at an average rate of 5 km/h coming back down.
 If the entire trip (not counting a lunch stop at the lookout) took approximately 2 hours and 15 minutes, what is the total distance the hiker walked?
 Round your answer to the nearest tenth of a kilometer.
:
Let d = the one-way distance
:
Write a time equation, time = dist/speed, change 2 hr 15 min to 2.25 hrs
:
{{{d/2}}} + {{{d/5}}} = 2.25
multiply by  10 to clear the denominators, results:
5d + 2d = 10(2.25)
7d = 22.5
d = {{{22.5/7}}}
d = 3.214 one way, 2(2.214) = 6.43 ~ 6.4 km, total distance
:
:
Check solution find the actual times
3.2/2 = 1.6
3.2/5 = .64
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total time: 2.24 ~ 2.25, confirms our solution