OT: Mathematical Conundrum II

Search me.

Reply to
Tim Streater
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Let the cost of the ball be x

Therefore the bat costs x+1 (working in £)

We know: cost of bat + cost of ball = 1.10

Substitute the costs we know:

x+1 + x = 1.10

So: 2x+1 = 1.10

So: 2x=0.10

So: x=0.05

Therefore cost of ball is 5 pence

Cost of bat is £1.05

Reply to
Brian Reay

You can't buy 2 metres; you have to buy 2.1m. Timber is sold by the "metric foot"

Reply to
charles

Suppose the angle grinder as a diameter of x inches

The circumference is about 3x (taking Pi as 3)

3000 rpm = 180000 r/hr

Therefore a point on the circumference travels 3x X 180000 = 5400000x inches in an hour.

With 5280 ft to the mile, call it 5400 (It just an estimate we need.

540000x/5400 miles per hour.

Or 100x.

So, multiple the diameter by 100 to get an estimate of the edge speed.

On that basis either the grind is small or he made an error.

Reply to
Brian Reay

He didn't, you did. You've mixed your inches and feet.

And other people have mentioned the speed is 11,000 RPM and diameter about 110mm. (4.5" angle grinder).

Reply to
Clive George

Oh, the irony - given the direction the thread's taken...

Reply to
Adrian

There are stones which are not 14 pounds.

Aha, Wiki manages a little table with the 15 pound wool stone - and others:

Commodity Number of Pounds Wool 14, 15, 24 Wax 12 Sugar and spice 8 Beef and mutton 8

Reply to
polygonum

My understanding of a guinea was it was was 21 shillings and used to pay auctioneers and other such persons as it included a 5% commission above the value of a "pound" for the auction house.. Perhaps I got that trinket of wisdom from Bargain Hunt or Flogit or whatever who knows...

Reply to
www.GymRatZ.co.uk

Ah, a fellow enthusiast. I dream about "kindling my desires with Mrs S under her tiger-skin duvet" :-)

Reply to
NY

So I did.

Either way the point was the method, ie no need to do much real mental maths.

Reply to
Brian Reay

Unless you're Dyslexic :)

Reply to
www.GymRatZ.co.uk

I'm sorry, but that is the WRONG answer. You were only asked to work out the cost of the ball, NOT the bat as well. ;->

Reply to
Cursitor Doom

If that's bad, try buying a tyre... width in mm, height as a percentage of width, and wheel diameter in inches.

Reply to
John Rumm

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