### Brain Teasers

# Grazing Cow

A cow is tied in a rectangular field, 20m by 10 m.

The cow is tied to the middle of one of the 20m long fences by a rope 25m long. There is a gap the cow can squeeze through in the middle of the other 20m long fence (assume a point).

How much land can the cow graze on?

The cow is tied to the middle of one of the 20m long fences by a rope 25m long. There is a gap the cow can squeeze through in the middle of the other 20m long fence (assume a point).

How much land can the cow graze on?

### Answer

He can get to the whole area of the field, + the area of a semi circle outside the field, and 2 areas of quarter circles where the rope extends around the sides of the fences.20*10 + (pi*15^2)/2 + 2* (pi*5^2)/4

200+pi*112.5 + pi*12.5

200 + pi * 125

Approx 593 square metres.

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## Comments

just a lil long for me well i am a blonde oh well good one for ppl who like to solve these kinds of problems. dont take it personally because i have an f in math

Fair enough!! I just don't really like the word puzzles. I either will get them straight away, or never in a million years!

I got it right in theory...

I just diddn't work out the pi bit

I just diddn't work out the pi bit

Very nice, quite creative!

I did it a little quickly in my head and didn't think about the quarter circles along the outsise of the short sides of the enclosure. Easy math, but creative.

Nice variation on an old theme.

finally, one I got! Nice teaser!

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