SOLUTION: Tom and Bill are standing at two places on a straight road. Tom starts walking toward Bill and arrives at Bill's original place 11 minutes after Bill had left. At perhaps a dif

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Question 1044595: Tom and Bill are standing at two places on a straight road. Tom starts
walking toward Bill and arrives at Bill's original place 11 minutes after
Bill had left. At perhaps a different time, Bill starts walking toward Tom
and arrives at Tom's original place 15 minutes after Tom had left. When
each reaches the other's original place, he immediately turns and starts
back, and they meet in the center at 4:00. Assuming that they walked at
constant rates, when did each start to travel on the road?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
t= time in minutes for Tom to walk to the center of the road
b= time in minutes for Bill to walk to the center of the road
Counting time in minutes starting at 4:00.
Tom left home at -3t (meaning 3t minutes before 4:00)
Bill left home at -3b (meaning 3b minutes before 4:00).
Tom arrived at Bill's at -t .
According to the problem that was -3b%2B11 , so -t=-3b%2B11<-->t=3b-11 .
Bill arrived at Tom's at -b .
According to the problem that was -3t%2B15 , so -b=-3t%2B15<-->b=3t-15 .
system%28t=3b-11%2Cb=3t-15%29--->system%28t=3b-11%2Cb=3%283b-11%29-15%29--->system%28t=3b-11%2Cb=9b-33-15%29--->system%28t=3b-11%2Cb=9b-48%29--->system%28t=3b-11%2Cb-9b=-48%29}--->system%28t=3b-11%2C-8b=-48%29--->system%28t=3b-11%2Cb=%28-48%29%2F%28-8%29%29--->system%28t=3b-11%2Cb=6%29%29--->system%28t=3%2A6-11%2Cb=6%29%29--->system%28t=7%2Cb=6%29%29
So, Tom left 3t=3%2A7=21 minutes before 4:00, at 60-21=39 minutes after 3:00, meaning at highlight%28%223%3A39%22%29 , and
Bill left 3b=3%2A76=18 minutes before 4:00, at 60-18=42 minutes after 3:00, meaning at highlight%28%223%3A42%22%29 .