Tuesday Puzzle.

[pete]

The fairground owner has 2 sons and a carousel, the floor of which needs painting.

As the paint costs a fortune the first job is to calculate how big the floor is so Son A is sent out to measure it. Now in the centre of the carousel is a circular room that contains all the machinery so there is no way of measuring from the centre of the carousel.
Panicking, the son takes a measurement from the edge of the carousel to another edge with his tape. Th tape touches the inner circle tangentially and the distance is 70 feet.

He goes back inside, rather sheepishly, with his measurement and suffers his father's ire.

"What the hell use is this?" asks the father.

"Hang on Dad" says Son B "I think I can work this out."

What is the area of the "annulus" or doughnut shaped floor area of the carousel?

[campbell]

3,846.5 sq ft

[pete]

3,846.5 sq ft

No

[David]

3,846.5 sq ft

No

Think it is ( near enough)

35 squared x pie =3848.45

[campbell]

3827.66 (Mrs Ford submission)

[David]

The area is constant irrespective of size - so if you reduce the the centre circle to zero you've got the diameter.

[pete]

3,846.5 sq ft

(That's what happens when you haven't worked out the answer yourself).

Yes. Puzzler courtesy of Car Talk...

[campbell]

Thanks!