Brain Teasers
Dog Circle
There is a 10-foot long rope that is tied between a hook on the ceiling and a hook on the floor. There is no slack in the rope. Jake wants to tie up his dog so he can go do a little shopping. He detaches the rope from the floor hook and attaches the free end to the dog's collar, which happens to be 2 feet off the floor because it's a big dog. The dog can now run around in a circle and because the rope goes to the ceiling the dog won't trip or get tangled up in the rope. What a good idea! What is the radius of the circle in which the dog can wander?
Hint
Draw a picture and remember your trigonometry.Answer
The dog can run in a 6-foot radius circle. To get the answer, first draw a right triangle. The long side (hypotenuse) is the length of the rope when fully stretched by the dog, 10ft. The medium side is the distance from the ceiling to the dog's collar, 8ft. The short side of the triangle is the radius of the circle. Using the Pythagorean Theorem (a^2+b^2=c^2) we can solve for this number.Hide Hint Show Hint Hide Answer Show Answer
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Comments
Nice.
You already know the Hypotenuse C=(10') and the medium side
A=(8'). So... C^2 - A^2 = B^2 which is... B=6'
A=(8'). So... C^2 - A^2 = B^2 which is... B=6'
Ugh...."Difficulty (3.66) "
Why? This is simple grade 6 Pythagorean Theorem peoples!
This is a 2.3 at the most...
Why? This is simple grade 6 Pythagorean Theorem peoples!
This is a 2.3 at the most...
I agree with Sane, but fun nevertheless.
I don't know TRIG !!!! WAAAA!!!!! Me only 10
It's just a 3-4-5 triangle. No real math necessary. Still fun, though.
Of course the real answer is slightly less than 6. If the rope is exactly 10 ft., the knots holding the rope to the ceiling and to the dog would lessen the relevant length.
I dont know trig, but still, musta took a while to think it up
Wow, i cant believe i didnt get it, and im in a really hard math class. Way to go on stumping me, keep em coming, i enjoyed the challenge of trying to figure it out!!
Nice one.
Good Teaser, Jake!
Yawn. Another 3-4-5 right triangle problem.
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