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jason_gee Send message Joined: 24 Nov 06 Posts: 7489 Credit: 91,093,184 RAC: 0 |
mode = 4 median = 4 mean = 3.78 , ( 102 / 27 ) statistical range = 8 "Living by the wisdom of computer science doesn't sound so bad after all. And unlike most advice, it's backed up by proofs." -- Algorithms to live by: The computer science of human decisions. |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Another correct answer by Jason! Q78 Answer : 4, 4, 3.78, 8. Standings: 1. William Rothamel - 20 1/2 Points 2. Fred W - 19 1/2 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... Another one of the same difficulty: Q79 (1/2 Point) : O, T, T, F, F, S, S, E, ? What is the nest letter in the sequence? Luke. - Luke. |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Another correct answer by Jason! Q79: N [edit] I assume you meant the next letter ;) [/edit] |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Fred Wins Question 79! Well done! :) - The Next Letter is the Answer ;) Question 79: N Standings: 1. William Rothamel - 20 1/2 Points 2. Fred W - 20 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... One last one before I'm off: Question 80 (1 Point) : Probability required. Suppose there are n people in an office. At Christmas they have a random gift exchange in which every name is writen on scraps of paper, mixed around in a hat, and then everyone draws a name at random to determine who they are to get a gift for. What is the probability nobody draws their own name? Luke. - Luke. |
Philadelphia Send message Joined: 12 Feb 07 Posts: 1590 Credit: 399,688 RAC: 0 |
Fred Wins Question 79! Well done! :) - The Next Letter is the Answer ;) It's going to vary depending on what the 'n' number of people is, so without knowing 'n' I don't think there is an answer. 1 point for noting a possible error, lol? [edit] Uh Oh, looks like I'm going to have to run a WU, I just noticed my RAC is '1', lol. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
Give the answer in terms of N |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Fred Wins Question 79! Well done! :) - The Next Letter is the Answer ;) Well the website I got this one says the answer is: The answer is 1/2! - 1/3! + 1/4! - 1/5! ... +/- 1/n!. Here is another Question 80: Q80 v2.0: Probability required. Given an ordinary deck of cards, what is the probability of drawing each kind of hand in poker? No discards, just the first five cards. Remember, aces can be high or low. Luke. - Luke. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
My grandmother taught me these she had the approximate numbers almost right. First take 52 x 51 x 50 x 49 x 48 =311,875,200 but these are the same regardless of order so divide by 5! -5*4*3*2*1=120 so (311,875,200)/ 120 =2598960 which is the number of unique hands. So allocating the appropriate hands to each category we get after much punching in on the calculator and adding in the appropriate inclusive hands and subtracting to get the remaining hands we have:s No pair even --a bust hand =50.1173 % of the time one pair = 42.25690 % 2 pair =4.753902 % 3 of a kind= 2.112845 % straight = .392465 % flush = .1965402 % full house =.1440576 % 4 of a kind =.0240096 % straight flush = .001385169 % Royal straight flush = .0001539077 % of the time--only 4 of the possible hands !! So if you add them all up I am a little off of 100% due to roundoff error--probably made a keying error along the way but looks about right to me. I don't like to do so much number crunching for these but poker is a love of mine. I got a Royal Flush the other day but it was in draw poker--also got 4 of a kind two years running at our summer family reunion --in each case the same guy had a good hand also and bet heavily --losing to my 4 of a kind --2 years in a row !! Regards, Bill |
Matthew Love Send message Joined: 26 Sep 99 Posts: 7763 Credit: 879,151 RAC: 0 |
Here is A simple math problem 4+4 = 8 ;O) LETS BEGIN IN 2010 |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Here is A simple math problem Depends on your number base. It could be 10 ;P F. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
Here is A simple math problem "Mr Nkrumah, don't put me on" Vaughn Meader on a JFK spoof record popular in the late 50's. |
Matthew Love Send message Joined: 26 Sep 99 Posts: 7763 Credit: 879,151 RAC: 0 |
Or 9-4 = 5 :o) LETS BEGIN IN 2010 |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well done to Bill! for correctly answering Q80 (Your answer came in at 100.0009436% - Close enough ;)!!! I also love poker! Fred better hurry up... hope he still plays! Standings: 1. William Rothamel - 21 1/2 Points 2. Fred W - 20 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... Q81 (1 Point) : If it takes Michael 20 hours to paint a house and it takes George 30 hours, how long will it take if they work together yet independently? Luke. - Luke. |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well done to Bill! for correctly answering Q80 (Your answer came in at 100.0009436% - Close enough ;)!!! I also love poker! Q81: 12 hours [edit] In 1 hour together they will paint 1/20 + 1/30 = 5/60 = 1/12 I was beginning to think it was a conspiracy of those that understand games of chance ;) [/edit] F. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
I just got up and saw an easy kill on the house problem--this is stuff I remember from way back in grade school. Then I saw Fred's post. One of my large, old Bradford Pear trees fell over entirely without reason and smashed a section of my neighbor's fence yesterday. My insurance company tells me I'm not covered since it didn't happen due to my negligence or during a storm or lightning strike. Plus my pool is still leaking and my kid's tuition bills are sitting on my desk and the head of the "university" where I was to teach this summer has left and left the place in disarray. My 14 year old cat had to be put down last week as well. I can't afford to drive 1250 miles round trip to our summer family reunion this year and my son is home from college and hasn't found a job for the summer yet as well. Reminds me of that old comedy record about never giving up the ship. It's all Fred's fault. back to bed now LOL, Bill |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well Done to Fred for solving Q81! Congratulations! Q81 Answer : 12 Hours Standings: 1. William Rothamel - 21 1/2 Points 2. Fred W - 21 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... Q82 : A loaded coin has probability of landing on heads of 0.6 and for tail 0.4. Winning bets on heads pay even money. With an initial fortune of $10 and betting $1 at a time what is the probability of eventual ruin assuming you kept playing until being ruined? Luke. - Luke. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
The probability of ruin would be simply P=(.4/.6) raised to the tenth power (2/3)^10 =(.6666666...)^10 which is .01734153 on my TI 36 calculator If you are checking my answer be sure to run 2/3 out to as many places as possible on your calculator since you are multiplying a decimal by itself ten times (actually used y^x). |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well done Bill! Q82 Answer: 0.1734 Q82 Solver: Bill Standings: 1. William Rothamel - 22 1/2 Points 2. Fred W - 21 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... A few more posts until a winner is drawn! Q83 (1 Point) : A spider eats 3 flies a day. Until the spider fills his quota a fly has a 50% chance of survival if he attempts to pass the web. Assuming 5 flies have already made the attempt to pass, what is the probability that the 6th fly will survive the attempt? Luke. - Luke. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
The probability that none of the five flies were eaten is obviously: (1/2)^5=1/32 There are 32 combinations that could occur for the 5 previous flies: like the poker problem the flies that are eaten could be eaten at any of the 5 possible "trials" so you must take the permutations for each situation. P(0) flies is 1/32 (P(1) is (5/1) * (1/32) =5/32 P(2) is (5x4)/(1x2)*1/32=10/32 So the probability that the spider might still be hungry-(less than 3 flies) is 1 -the sum of the above So 1-(1/32 +5/32+10/32)= 1-(16/32)= 1-1/2 =1/2 So: Probability =.5 that he is still hungry after five flies have gone by the web This means of course that the probability that he is full is also .5 So the probability of a successful pass is the joint probability that he is full plus the probability if he is hungry and the fly still has the 50% chance This is 1/2 +[(1/2)*.5) = 1/2 + 1/4 =.75 ANSWER =.75 |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
That's correct Bill! Well Done! Q83 Answer: 75% Standings: 1. William Rothamel - 23 1/2 Points 2. Fred W - 21 Points 3. Guido.Man - 10 Points 4. Mr. Kevvy - 7 Points 5. Dominique - 6 1/2 Points 6. Philadelphia - 6 1/2 Points 7. WinterKnight - 6 Points 8. Sarge - 5 1/2 Points 9. Jason gee - 4 1/2 Points 10. John McLeod VII - 1 Point 11. Labbie - 1 Point 12. Scary Capitalist - 1/2 Point 13. TBD... Your still in this Fred! Q84 : What is the volume of an octahedron with edge length of 1? Luke. - Luke. |
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