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| Thread ID: 51116 | 2004-11-12 02:56:00 | OT-NZCA MATH | Dally (6292) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 290842 | 2004-11-12 07:36:00 | The number of sports played at Olympic games 40 years ago = 19! :D Stuff the math formulas - google tells all (www.cbc.ca) :p |
Jen C (20) | ||
| 290843 | 2004-11-12 07:37:00 | snap :p |
andrew93 (249) | ||
| 290844 | 2004-11-12 07:38:00 | Andrew93> SNAP! :^O | Jen C (20) | ||
| 290845 | 2004-11-12 07:39:00 | they are not going to base it on a real thing - wat if you knew that all you will have to do is make the equation | ApeNz (4220) | ||
| 290846 | 2004-11-12 07:40:00 | Almost word for word to - plus the timing of the snap :^O |
andrew93 (249) | ||
| 290847 | 2004-11-12 07:45:00 | The question you posted is actually quite clear and easy to understand. I have seen others which are very bad however. | somebody (208) | ||
| 290848 | 2004-11-12 07:51:00 | I don't what to appear a smart alec but here is the approach my old math teacher advocated Let x = number of sports 40 years ago Then average number of competitors per sport = 5x Average number of competitors per sport in 2004 = 17.5x No of sports in 2004 = (x + 10) No of competitors in 2004... 17.5x(x + 10) = 10500 Simplify ... x.x + 10x - 600 = 0 x = +20 or -30 Reject -30 as applicable perhaps only in Discworld Number of sports in 1964 = 20 Close to the actual it seems |
Dally (6292) | ||
| 290849 | 2004-11-12 08:14:00 | Ave Comp. per sport 1964 = X Ave Comp per sport 2004 = Y Number of sports 1964 = A Number of sports 2004 = B BY = 10500 B x (3.5X) = 10500 B x 3.5(5A) = 10500 A+10 x 3.5(5A) = 10500 (A+10) x 17.5A = 10500 17.5A^2 + 175A = 10500 A^2 + 10A = 600 A^2 + 10A -600 = 0 Factorise (A+30)(A-20) = 0 solve = -30 or 20 since cannot be -ve, then must be +20 So answer = 20. And I think this works (I substituted it back in to check) |
somebody (208) | ||
| 290850 | 2004-11-12 08:15:00 | aargh.. too slow. | somebody (208) | ||
| 290851 | 2004-11-12 08:19:00 | > I don't what to appear a smart alec you don't have to worry about that :D (you said it) > but here is the > approach my old math teacher advocated > Let x = number of sports 40 years ago > Then average number of competitors per sport = 5x > Average number of competitors per sport in 2004 = > 17.5x > No of sports in 2004 = (x + 10) we all agree up to this point > No of competitors in 2004... 17.5x(x + 10) = 10500 the number of competitors is not the average number of competitors for 2004 multiplied by the number of sports in 1964 multiplied by the number of sports in 1964 less 10. You have got yourself confused there between "x" the variable and "x" being the multiplier - it should be : 2004 competitors = 17.5 times ("x" + 10) = 10500 > Simplify ... > x.x + 10x - 600 = 0 17.5x times (x + 10) actually simplifies to 17.5 times x squared plus 27.5x > x = +20 or -30 > Reject -30 as applicable perhaps only in Discworld And so the error now compounds. Why didn't you use the factors -20 and +30? They yield the same product.... > Number of sports in 1964 = 20 We all know it's 19 but hey....what's one sport? > Close to the actual it seems So to summarise your maths : x = 20 Sports04 = 600 Sports04 = x + 10 so 600 = 20 + 10???? You guys are learning some really weird maths..... x=590, see my previous post case closed! |
andrew93 (249) | ||
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