| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 507.1 | | BEING::POSTPISCHIL | Always mount a scratch monkey. | Wed Jun 11 1986 15:34 | 26 |
| Let Jill start at time 0, position 0. Let Dave start at time t,
position d.
> Jill starts walking toward Dave and arrives at Dave's original place 11
> minutes after Dave had left.
Let v = Jill's velocity. Then d/v = t + 11 minutes.
> Dave (starting at perhaps a different time) walks toward Jill and
> arrives at Jill's original place 15 minutes after Jill had left.
Let w = Dave's velocity. Then d/w = 15 minutes.
> When each reaches the other's original place, he or she immediately
> starts back, and they meet in the center at 4:00 p.m.
Let T be the total time taken (it also represents 4:00 p.m.) since
Jill started. By this time, Jill and Dave have both walked the
distance d, turned around, and walked to the center, for a total
distance of 3/2 d, so (T-t)w = 3/2d = Tv.
These equations are fairly simple to solve; Jill started at 3:25:30
and Dave started at 3:37:30.
-- edp
|
| 507.2 | slow down, Dave | LATOUR::JMUNZER | | Wed Jun 11 1986 15:59 | 3 |
| But, in .1, Dave will turn at 3:40:30, and try to meet Jill at 3:42.
John
|
| 507.3 | re .1 | ZEPPO::DAY | | Wed Jun 11 1986 15:59 | 5 |
|
Something is wrong somewhere - that's not quite it.
|
| 507.4 | Correction | BEING::POSTPISCHIL | Always mount a scratch monkey. | Wed Jun 11 1986 16:49 | 27 |
| Let Jill start at time 0, position 0. Let Dave start at time t,
position d.
> Jill starts walking toward Dave and arrives at Dave's original place 11
> minutes after Dave had left.
Let v = Jill's velocity. Then d/v = t + 11 minutes.
> Dave (starting at perhaps a different time) walks toward Jill and
> arrives at Jill's original place 15 minutes after Jill had left.
Let w = Dave's velocity. Then d/w = 15-t minutes. (I had d/w = 15
here.)
> When each reaches the other's original place, he or she immediately
> starts back, and they meet in the center at 4:00 p.m.
Let T be the total time taken (it also represents 4:00 p.m.) since
Jill started. By this time, Jill and Dave have both walked the
distance d, turned around, and walked to the center, for a total
distance of 3/2 d, so (T-t)w = 3/2d = Tv.
These equations are fairly simple to solve; Jill started at 3:39
and Dave started at 3:42.
-- edp
|
| 507.5 | What a long walk.... | VOGON::CATTERMOUL | Richard REO F/M8 830-4564 | Wed Jun 18 1986 16:07 | 5 |
| A nice puzzle to do during the morning coffee break.
Jill starts off at 8.42 p.m. the previous evening
Dave starts off a little earlier at 8.31 p.m.
[Solution available on request]
Clue: similar triangles on a distance/time graph.
|