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"Simple" Maths Problems II
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jason_gee Send message Joined: 24 Nov 06 Posts: 7489 Credit: 91,093,184 RAC: 0 |
--> 363 / 850.5 = 726 / 1701 = 242 / 567 ~= 0.4268 "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. |
Fred J. Verster Send message Joined: 21 Apr 04 Posts: 3252 Credit: 31,903,643 RAC: 0 |
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Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well Done to Jason! Winterknight following close behind. Don't worry 'bout it, Fred!!! It's nice to have you here! Jason Gee wins Question 4, well done! Question 4 Answer: 0.4268 Standings: 1. Fred - 1 Point 2. Jason Gee - 1 Point 3. The Gas Giant - 1/2 Point 4. TBD... Question 5 (1/2 Point): (876x2.4)+(1976-432x1.2)=??? Luke. - Luke. |
The Gas Giant Send message Joined: 22 Nov 01 Posts: 1904 Credit: 2,646,654 RAC: 0 |
3560 |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
3560 Well Done Gas Giant! Can you solve this one?... Standings: 1. Fred - 1 Point 2. Jason Gee - 1 Point 3. The Gas Giant - 1 Point 4. TBD... Question 6 (1 Point): On the first day of a new job, a colleague invites you around for a barbecue. As the two of you arrive at his home, a young boy throws open the door to welcome his father. “My other two kids will be home soon!†remarks your colleague. Waiting in the kitchen while your colleague gets some drinks from the basement, you notice a letter from the principal of the local school tacked to the noticeboard. “Dear Parents,†it begins, “This is the time of year when I write to all parents, such as yourselves, who have a girl or girls in the school, asking you to volunteer your time to help the girls' soccer team.†“Hmmm,†you think to yourself, “clearly they have at least one of each!†This, of course, leaves two possibilities: two boys and a girl, or two girls and a boy. Are these two possibilities equally likely, or is one more likely than the other? Note: This is not a trick puzzle. You should assume all things that it seems you're meant to assume, and not assume things that you aren't told to assume. If things can easily be imagined in either of two ways, you should assume that they are equally likely. For example, you may be able to imagine a reason that a colleague with two boys and a girl would be more likely to have invited you to dinner than one with two girls and a boy. If so, this would affect the probabilities of the two possibilities. But if your imagination is that good, you can probably imagine the opposite as well. You should assume that any such extra information not mentioned in the story is not available. Luke. - Luke. |
The Gas Giant Send message Joined: 22 Nov 01 Posts: 1904 Credit: 2,646,654 RAC: 0 |
Hmmm....a stab in the dark says that the probability is higher that in total there is one boy and two girls. Assumptions here are: 1. Something in the way the father says, my other two kids will be home soon. Maybe they're at the girls soccer practice. 2. Girls' soccer team v girls soccer team. Does this imply they have 2 girls.... Anywho.... |
jason_gee Send message Joined: 24 Nov 06 Posts: 7489 Credit: 91,093,184 RAC: 0 |
Given one boy, the remaining children could be either boy & girl, or two girls, so the possible combinations are: Boy Girl Boy (1/3) Boy Boy Girl (1/3) Boy Girl Girl (1/3) So there's two thirds chance the colleague has two boys & a girl, and one third chance the colleague has one boy and two girls. Jason [P.S. Lovely story about soccer teams and stuff, but I think it has little bearing on the possibilities other than to say at least one of the remaining kids is a girl] "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. |
The Gas Giant Send message Joined: 22 Nov 01 Posts: 1904 Credit: 2,646,654 RAC: 0 |
Given one boy, the remaining children could be either boy & girl, or two girls, so the possible combinations are: Ahh..I'd have to agree with that. |
W-K 666 Send message Joined: 18 May 99 Posts: 19065 Credit: 40,757,560 RAC: 67 |
You could have three boys, because the teacher did not know difference between Lesley and Leslie. |
jason_gee Send message Joined: 24 Nov 06 Posts: 7489 Credit: 91,093,184 RAC: 0 |
You could have three boys, because the teacher did not know difference between Lesley and Leslie. I think they also have an ambiguous gender soccer team :D "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 |
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Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Can you be consistent with symbols, please? Is mutiplication "x" or "*"? F. |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Multiplication = x Division = * Luke. - Luke. |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Hmmm. Thanks. First time I've seen that symbol used for division. In that case, shouldn't this question be worth 1*2 Point? F. |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Lol, 1/2 refers to the fraction... In NZ we use +,-,x,*... Luke. - Luke. |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Interesting. I wonder how widespread that usage is? I have only ever come across the * used for multiplication. BTW, I believe the answer to be 2214.933333... F. |
JDWhale Send message Joined: 6 Apr 99 Posts: 921 Credit: 21,935,817 RAC: 3 |
Well Done to Jason Gee!... 1 Point... He takes the lead... 2216.53333... |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well Done to Jason Gee!... 1 Point... He takes the lead... Good spot, JD. That's what comes of trying to do it in my head :( F. |
Luke Send message Joined: 31 Dec 06 Posts: 2546 Credit: 817,560 RAC: 0 |
Well Done to JDWhale! 1/2 Point to you... Standings 1. Jason Gee - 2 Point 2. Fred - 1 Point 3. The Gas Giant - 1 Point 4. JDWhale - 1/2 Point 5. TBD... As to be consistent to American markup... Addition = + Subtraction = - Multiplication = * Division = / Question 8: 1/2 a Point: (220*3.4/18)*(821/13)=? Luke. - Luke. |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
Well Done to JDWhale! 1/2 Point to you... Q8: 2624.2678 to 4dp. F. |
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