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October 1st, 2004, 6:25 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

<t>What makes you think someone meant that the max speed comes from "hits the ball as hard as he can"? Other than that your estimation based on the reaction time is an excellent point. The question is: is there anything else that could limit the ball speed more than a reaction time? I don’t see anyt...
October 1st, 2004, 5:04 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

<t>exotiq,Of course I mean the speed of the ping-pong ball relative to the surface of the table on a space ship where green aliens in a shape of a suitcase consume hamburgers (I can only imagine what happens to hamburgers in two hours after traveling through aliens bowels) while the ping-pong table ...
October 1st, 2004, 4:01 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

QuoteOriginally posted by: exotiq1. The speed of light, c4. Because they're still alive in the salty ocean, and are best eaten as sashimi a very short time after removal.1. Let's be real.
October 1st, 2004, 3:59 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

QuoteOriginally posted by: mdubuqueFor number 2 would the distance between your eye sockets matter?MatthewTry to close one eye. Is there any difference?
October 1st, 2004, 3:57 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

<t>QuoteOriginally posted by: tristanreid1. About 75 mph?2. a function of your height off of the ground and either the curvature of the earth, the real distance between the lines, or the angle at which they appear to join. Probably about 3.5 miles.3. i don't understand the question4. the cell membra...
September 30th, 2004, 2:56 pm
Forum: Brainteaser Forum
Topic: Some puzzles
Replies: 15
Views: 174384

### Some puzzles

<t>1. Two men are playing Ping-Pong. What is the estimation for a max speed of a ball?2. How would you estimate the distance where you see two parallel lines joining?3. Earth and Moon. How would you estimate the change in day+night duration for Earth dew to a gravitational friction? The Moon has “st...
September 3rd, 2004, 5:31 pm
Forum: Brainteaser Forum
Topic: Coin flipping again - the true story
Replies: 13
Views: 178107

### Coin flipping again - the true story

What is the standard deviation from N*p*(1-p)?
September 2nd, 2004, 5:48 pm
Forum: Brainteaser Forum
Topic: Coin flipping again - the true story
Replies: 13
Views: 178107

### Coin flipping again - the true story

N*p*(1-p) second that.
August 20th, 2004, 5:43 pm
Forum: Brainteaser Forum
Topic: the grainy chart
Replies: 26
Views: 180271

### the grainy chart

I assume when you toss an "infinite coin" you get a one side up out of infty. Then here is a "paradox": what is the probability to get a particular side of an "infinite coin" when you toss it? Zero. How come then when tossing it you choose one side with a probability 1?
August 18th, 2004, 4:16 pm
Forum: Brainteaser Forum
Topic: the grainy chart
Replies: 26
Views: 180271

### the grainy chart

Ok: If all you know is that the 1000 recent ticks on the chart were all upticks, what is the probability that the next tick out of the bag will be an uptick? It's clear now that it's 1/2, isn't it?
August 18th, 2004, 2:30 pm
Forum: Brainteaser Forum
Topic: birthday
Replies: 12
Views: 178841

### birthday

August 18th, 2004, 1:10 pm
Forum: Brainteaser Forum
Topic: birthday
Replies: 12
Views: 178841

### birthday

n>365 then the probability is 1.
August 17th, 2004, 5:31 pm
Forum: Brainteaser Forum
Topic: the grainy chart
Replies: 26
Views: 180271

### the grainy chart

<t>Tripitaka, that is my way of reasoning as well initially, except assuming binomial distribution I get 1/16 1/4 3/8 1/4 1/16 right away. I also got surprised, but I’ll tell you even more: the probability of 3 ups in a row is the same as 3 down of course, the same as 1st up, 2nd down and 3rd up aga...
August 17th, 2004, 2:45 pm
Forum: Brainteaser Forum
Topic: the grainy chart
Replies: 26
Views: 180271

### the grainy chart

QuoteOriginally posted by: Feanorerr change that to 41%sorry Would you mind to share your calculation? According to my reasoning the probability of next uptick is the same as the probability of next downtick.
August 16th, 2004, 4:53 pm
Forum: Brainteaser Forum
Topic: the grainy chart
Replies: 26
Views: 180271

### the grainy chart

<t>Let’s look at the grainy chart. The probabilities to choose uptick or downtick from the chart are equal and are ½. What is the probability to choose two upticks in a row from the grainy chart? It’s the same as to choose two downticks, or uptick following downtick, or downtick following uptick and...

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