Round 2 30/09/2018 Home
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[ 10 points ] How many positive integers smaller than 2018000 have an odd number of factors?
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[ 25 points ] Alice has a large number of 12c, 17c and 19c coins. What is the largest price for which she cannot pay the exact amount?
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Consider the four numbers:
\[2^{2^{2^{2^2}}},3^{3^{3^3}},4^{4^4},10^{1000}\]
[ 15 points ] How many digits does the smallest number have?
[ 25 points ] How many digits does the largest number have?
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[ 25 points ] Suppose a keyboard has all the letter keys, along with spacebar, question mark, comma and full stop. What are the first five significant digits of the chance that a monkey randomly hitting this keyboard would type out this question?
Note: Ignore the point tally, this note and case (e.g lowercase/uppercase) in your answer.