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wooneh

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Jun 30th, 2014
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  1. To adeebnafees: The diameter of a car's back wheels are one and a half times the diameters of the front wheels. When the car travels one metre, the back wheels go around 6 times. How many times do the front wheels go around when the car travels one meter?
  2. AdeebNafees: Your physical chains are nothing to the physical might of the bed.
  3. AdeebNafees: Cya!
  4. AdeebNafees: So circumference of back wheel is 1/6 (reply)
  5. AdeebNafees: If the diameter is one and a half times as great, so is the circumference (reply)
  6. AdeebNafees: So the circumference of the front wheel is 1.5/6 (reply)
  7. AdeebNafees: Oh no, wait, the front sheels are 1.5 times smaller (reply)
  8. AdeebNafees: Some 0.111 meters I think (reply)
  9. AdeebNafees: So you divide 1 by 1.111 (reply)
  10. AdeebNafees: Some 9 times I think (reply)
  11. To AdeebNafees: yay
  12. To adeebnafees: I cut my finger :(
  13. AdeebNafees: *puts bandage on* (reply)
  14. To AdeebNafees: d'aww
  15. To adeebnafees: Let R be a set of nine distinct integers. Six of the elements are 2, 3, 4, 6, 9, and 14. What is the number of possible values of the median of R ?
  16. AdeebNafees: Ooh, interesting. (reply)
  17. AdeebNafees: The remaining three integers can occupy either the space below 2, [5, 7, 8, 10, 11, 12, 13] or numbers above 14. (reply)
  18. AdeebNafees: If all of them are below 2, 3 will be the new median value. (reply)
  19. AdeebNafees: If all of them are above 14, 9 will be the median value. (reply)
  20. AdeebNafees: 2 and 14 are thus never the correct median value. (reply)
  21. AdeebNafees: This implies that the range of possible values will be somewhere from 3 to 9. (reply)
  22. AdeebNafees: There are only 7 possible values: 3, 4, 5, 6, 7, 8, 9 (reply)
  23. AdeebNafees: However, all are not possible. (reply)
  24. AdeebNafees: 3 and 9 have been demonstrated to be possible. 4 is not possible as it cannot be the central value for any distribution of integers. (reply)
  25. AdeebNafees: 5 is possible as we get 7 values at that time and can place two other values behond 2 and 14. 7, again, is possible since there are 9 values in all. (reply)
  26. AdeebNafees: 8 is possible for a similar reasoning. (reply)
  27. AdeebNafees: So the possible values, I'd hazard, are 3, 5, 6, 7, 8 (reply)
  28. AdeebNafees: This is actually, come to think of it, a rearrangement puzzle. (reply)
  29. AdeebNafees: "How many numbers can you have which will have 4 numbers on either side provided the current numbers" (reply)
  30. AdeebNafees: For 2 and 14, we already have 5 numbers on each side. (reply)
  31. AdeebNafees: Wait a second. 4 is possible. (reply)
  32. AdeebNafees: 0, 1, 2, 3, 4, 6, 9, 13, 14 (reply)
  33. AdeebNafees: So the correct range of values is from 3 to 9, inclusive. (reply)
  34. To AdeebNafees: good
  35. To AdeebNafees: The first and seventh terms of a sequence are both 8. Each term of the sequence is the sum of the two previous terms. What is the fifth term?
  36. AdeebNafees: Taking x as second term. 8+x is the 3rd term. 8+2x is the 4th. 16 + 3x is the 5th. 24 + 5x is the 6th. 40 + 8x is the seventh. But 40 + 8x = 8. So 8x = -32. Therefore x = -4. (reply)
  37. AdeebNafees: Therefore 5th term = 16 - 12 = 4 (reply)
  38. To AdeebNafees: icas
  39. AdeebNafees: Wut is that Malay? (reply)
  40. To AdeebNafees: what is 3+4
  41. AdeebNafees: Depends on the base of the number system you are using. (reply)
  42. AdeebNafees: In base 7, that's 10/ (reply)
  43. To AdeebNafees: A stone weighs 2.5N. When it is fully submerged in a liquid, its apparent weight is 2.2N. Calculate the density of liquid if its volume displaced by the stone is 25cm^3.
  44. AdeebNafees: The liquid is exerting an upward force of 0.3N, which is the weight of the displaced liquid (25cm^3). But weight is related to mass by good old g. (reply)
  45. AdeebNafees: So we have the volume of the displaced liquid AND its mass. (reply)
  46. AdeebNafees: Some 1.2k kg/m^3 I think (reply)
  47. AdeebNafees: Or 1.2g/cm^3, if you are into CGS (reply)
  48. AdeebNafees: I would guess the liquid to be glycerol, which has a density very close to 1.2g/cm^3 (reply)
  49. AdeebNafees: (courtesty Wikip) (reply)
  50. To AdeebNafees: If y(x) = u(x) v(x) w(x) with y, w, u, v as functions of x, prove that y' = u(x) v(x) w'(x) + u(x) v'(x) w(x) + u'(x) v(x) w(x)
  51. AdeebNafees: I just need to prove the basic product rule, which automagically proves the above. (reply)
  52. AdeebNafees: And seriously, I have proved the product rule like thousands of times. It involves a rearrangement midway. (reply)
  53. AdeebNafees: Oh, and you need to add a term midway. (reply)
  54. AdeebNafees: *add-subtract (reply)
  55. To AdeebNafees: How many pineapples does it take to feed an elephant?
  56. AdeebNafees: To be more specific, d/dx(f(x)g(x)) = lim [h->0] f(x+h)g(x+h)-f(x)g(x)/h (reply)
  57. AdeebNafees: It depends on the time of the day and the mood of the elefun. (reply)
  58. KADleon: Swag (reply)
  59. To adeebnafees: what did you eat
  60. To lethalmutiny: Evening. Lunch?
  61. LethalMutiny: no (reply)
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