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# dgreening

Member Since 24 Jun 2013
Offline Last Active Nov 18 2014 02:40 PM

### In Topic: Alice and Bob's marathon

12 November 2014 - 03:32 PM

Spoiler for

### In Topic: Fully Empty

03 November 2014 - 08:48 PM

Spoiler for Because Clair is a liar she cannot say that it is half full/ half empty

### In Topic: Random points on x-axis

08 October 2014 - 07:01 PM

'Could be over thinking this'

Spoiler for

Could be over thinking this!

for any 2 positive numbers A and B, there are just 3 possible
relationships

•
• A = B
•
• A > B
•
• A < B

If we assume that the range of numbers is really large then the P [A =
B]  is very, very low.

If we say that P [A=B] = 0, then there are just the 2 choices [A>B or
A<B] the relative magnitude of the numbers doesn't matter

and it is simply a matter of which number was chosen first.

A random process is just as likely to pick "small then large" as it is to
pick "large then small" and the P [A>B] = P[A<B] = 0.5

this holds whether the 2 numbers are (1 and 2) or (1 and a trillion)

[/spoiler]

### In Topic: From 16 points, how many ETs?

10 September 2014 - 01:55 PM

Clarifying question: Do we get to choose the positions of the fixed points??

### In Topic: Cars

12 August 2014 - 05:18 PM

Bill and William have decided to pull out his old cars from garage, in order to try how fast still they are. They did everything in form of contest, so they have dealed to stand in the start line and do a certain distance with cars in full throttle. Of course win that one, who reach the finish line first. When they reached the finish line they found out, that the car of Bill is 1,2 times faster, than the car of William. William has reached the finish line about 1 minute and 30 seconds later, than Bill. The bill´s car has reached in this given distance 60km/h speed in average.
The question is: How long have to be this distance that they have passed, if we know the above said data? Enter the result in kilometers.

Spoiler for