# Wikipedia:Reference desk archive/Mathematics/2006 August 7

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## Engine math.

I have a new rotary piston patent at :AdvanceEnergySystem.com Please check it out. Here is what I did: If you have a 1x1in. piston traveling in a circle on a rotor 12in. diameter.

at 600psi the torque is (((1x1)x6)x600)/12= 300 foot pounds, at 3600 rpms (=300x3600)/33000=32.73hp say this was steam power. Would this be the most powerful motor?

The piston travels 350 degrees before exit out of the exhaurst port.. I think this is the best way to go. If this was a gas version the power would be over 196.36hp. at 3600 rpms with 1800 psi. Am I wrong?

Is this really a maths question? Maybe you should try posting this question at Wikipedia:Reference desk/Science.  --LambiamTalk 14:58, 7 August 2006 (UTC)

## Inch pounds and foot pounds of torque

How many inch pounds of torque in one foot pound of torque

See [1]. Does that help ? --DLL 19:38, 7 August 2006 (UTC)
Or, if you want to be more verbose and get the same result, [2] Oskar 19:49, 7 August 2006 (UTC)

12in =1 foot. —The preceding unsigned comment was added by Tommey (talkcontribs) 20:42, August 7, 2006 (UTC).

## identical tiles

Rectangular floor is fully covered with tiles of identical size.Tiles on the edge are white and the tiles in the interior are red.The number of white tiles is the same as the number of red tiles.A possible value of the number of tiles along one edge of the floor is ...... 1. 10 2. 12 3. 14 4.16--203.145.188.130 17:13, 7 August 2006 (UTC)sourabh

If there are M by N tiles, you have MN total tiles and (M–2)(N–2) interior tiles. The puzzle says that half the tiles are interior, so the total is twice the number of interior tiles:
MN = 2(M–2)(N–2),
which can be rewritten as
(M–4)(N–4) = 8.
So in a solution the lengths in tiles of the edges are 4 more than a factor of 8. The factors of 8 are 1, 2, 4, and 8. The possible answers are then 5, 6, 8, and 12. More precisely, you can have 5 by 12 tiles, or 6 by 8 tiles. --LambiamTalk 17:55, 7 August 2006 (UTC)