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L.O. Investigating perimeter - finding all possibilities
Sir Rubin has a horse pen which uses 36 m of fencing.
One night, during a storm, the horse pen is destroyed.
The knight wants to re-build the rectangular pen,
but has only 36m of fencing and cannot remember
the exact dimensions from the first pen.
Can you help ?
Remember:
• the pen is rectangular
• only 36m of fence can be used
L.O. Solving mathematical puzzles and problems
Sir Rubin finds some extra fencing. He builds a
rectangular enclosure like this……
4 + 20 + 4 + 20
His squire, Neil, builds another enclosure with the
perimeter of….
7 + 17 + 7 + 17
How much fencing have they used ?
Sir Rubin says to Neil, “That’s not right. Your horse
has got more grass to eat than mine.”
Neil replies,” That can’t be true. Mine can’t have
more grass because we both used the same amount
of fencing.”
Have both goats got
the same amount of
grass?
Sir Rubin and Neil need to find out how to make the
rectangle of fencing using 48m so that each of their
horses gets the greatest amount of grass possible.
Can you help them?
L.O. Solving mathematical puzzles and problems
·
The knight checks and he has exactly £134 to
build a new rectangular enclosure.
He wants to enclose as much grass as possible so that
both horses can share the space.
· He decides to buy a fence
post for each corner of the
rectangle and twine netting
for the fencing.
Fence posts cost £3.50 each.
Twine netting costs £2.00 per
metre.
How long and wide should the rectangle be so
the horses can have as much grass as
possible?