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Easy math quiz

  1. Nov 18, 2006 #1


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  2. jcsd
  3. Nov 18, 2006 #2
    I though that was pretty interesting. Although the answers were not that close to eachtoher, most of them could be logically guesses. I took some extra time on the last one though.
  4. Nov 18, 2006 #3
    Their answer: (hidden text) 58
    The answer depends on how the steps are taken. For instance, if she takes two steps forward and then one back and repeats this pattern, it takes 56 steps, but this is not one of the choices. If she takes one step back and then two forward amd repeats this pattern, then it takes 60 steps. If she takes one step forward, one backward, and then another forward, and repeats this pattern then you get the answer required. And of course, if she takes 20 steps forward followed by 10 backward then it takes her 20 steps.

    My wife answered "I don't know" for all 5 questions, and in each case she was correct, but she got an F.
  5. Nov 18, 2006 #4


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    4/5, question 3 was odd as described above. Intuitively for me, one step back for every 2 forward = 2 forward then 1 back.

    Think of it as a trigger: "if you have taken 2 forward steps, take 1 reverse step".
  6. Nov 18, 2006 #5


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    3 could be interpreted at least two ways. Fortunately, one of the ways wasn't listed as an answer.

    4 is annoying for an ostensibly "do in your head" test, since the right answer is very close to a wrong answer. I didn't feel like squaring 3-digit numbers in my head, so I guessed that I rounded up more than I rounded down when getting my estimate of 158. :grumpy:
  7. Nov 18, 2006 #6


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    Hmm, that doesn't work. If the trigger is tested after each move, it would take more steps, * in fact. Perhaps that is how they meant it to be understood.

    *: don't know how to make it white.
    Last edited: Nov 18, 2006
  8. Nov 18, 2006 #7
    On the last one I just used the cost/guest. It was pretty easy to round it off and get an answer. 0.89/lb ~ 0.9/lb, 0.9/lb * 3/4 lb/guest < (but close to) .7/guest.
    Last edited by a moderator: Nov 18, 2006
  9. Nov 18, 2006 #8
    Yeah I took issue with number 4 as well Hurkyl

    For number 5 I thought the easiest was 3/4 of 18.

    3 was another issue, but as has been said one interpretation was not one of the choices.
  10. Nov 18, 2006 #9


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    3 is one of those brain teasers you hear from time to time. Oddly, they didn't put the trick answer.

    I did 4 using a calculator because I don't need to square two three digit numbers then take the square root of the sum in my head to know 157 is too close to 161 to make that an easy job.

    5 was a bit funny: the pounds value was different for each answer! Who would bother calculating the rest of the stuff??
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