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1/3 of the time, the door to heaven will be chosen, so 1/3 of the time it will take zero days. 1/3 of the time, the 1-day door is chosen; of those, the right door will be chosen the next day, so 1/9 trips take 1 day. Similarly, 1/9 will take two days (choosing the 2-day door, then the right door).
After that, the cases split again, and again, and again. I can’t seem to make a nice infinite sum this way, so let’s try again.
Suppose the average days spent is X. 1/3 of the cases are done in zero days as before. 1/3 of the cases are 1 day plus X. 1/3 are 2 + X. So:
X = 1/3 * 0 + 1/3 * (1 + X) + 1/3 * (2 + X)
= 0 + 1/3 + X/3 + 2/3 + X/3
= 1 + 2X/3
Therefore,X/3 = 1
X = 3
On average, it takes three days to get to heaven. Two if the noodles are limp.Took me one blind alley, and about five minutes.
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The main issue here is that an addition of odd numbers for odd times will result in an odd number. So in no way will you get an even number like 30 by adding these odd numbers.
So you will have to think out of the box to solve this one.Use of mathematical operator is a must.
To get an even number from an odd number the best operation to use would be factorial.
So we use 3!,
3! = 3 x 2 x 1 = 6
so if we add 3! five times we get the answer as 30. (As repetition of the number is allowed.)
Hence the answer would be;3! + 3! + 3! + 3! + 3! = 6 + 6 + 6 + 6 + 6 = 30.
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you will never find an elephant with one hand
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you will never find an elephant with one hand
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Lunch and dinner
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He will sleep at night,,!
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3rd path leads to the gift
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I think that it was cement below the bricks
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A dog with one of its legs amputated. ?
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