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It is great that so many of you really enjoyed
this problem, particularly the pupils of Canon Palmer Catholic
School.
We have had an entertaining time reading
your stories. Some of you made the problem more interesting by
moving both the sheep and the man, and looking at relative
distance.
Our favourites are shown
below:
Graph One
The first one is anonymous:
2 weeks ago there was a mad shepherd, who lived on a farm in the
middle of nowhere. His name was Dan.
There was another farmer down the road called James and every year
they had a contest to see who had shaved off the most wool.
Dan was behind because his sheep kept running away, so he started
to hi-jack James' sheep and take his wool.
But one day James made a plan to stop him taking his sheep: he put
a long row of wet cement on the ground so that when Dan went across
he would get stuck.
But when this happened not only Dan got stuck, but so did the sheep
and they were stuck there for 2 hours.
In graph one, the distance between the man
and the sheep is always the same. The story above describes the
sheep and the man being stationary over time. Here is another
story, this time from Sebastian of Canon Palmer Primary School, who
tells a rather gory story...
There once was a farmer a very bad farmer who killed sheep. I know
what you're thinking: "If you're a farmer then you have a right to
kill sheep."
Well he didn't kill his own sheep, he stole the little cutie ones
people keep as pets.
He was so bad that he went to prison for six years.
When he got back he got a court order so that he couldn't go closer
than four metres near to a sheep.
That is why the man is always the same distance from the
sheep.
When the man and the sheep keep the same
distance between them, are they walking in straight lines, or could
the man be walking in circles?
Graph
Two
Well done to Neha who has made up a nice story
to accompany graph two, which illustrates the man moving away from
the sheep at a steady speed.
Farmer Ted is very good with sheep. One day he goes to feed
the sheep but realises they are not there. He runs around the farm
not realising that the sheep are hiding behind the shed.
He goes further and further away from the sheep.
It has been minutes and the farmer thinks that his sheep might
have actually escaped the farm altogether. He runs out of the farm
and he is still searching right this minute...
Graph
Three
Thank you to Vipanjeet, who gives a scenario
for graph three. Here a man walks away from a sheep at a steady
speed, and then returns.
The man is walking to the river to feed his sheep.
When he is half-way there he remembers that he left the sheep
behind. So when he gets back it is too dark to go to the river and
feed the sheep.