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dark_magician_92

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Posts posted by dark_magician_92

  1. For every prime number (p) greater than 3, there exists a natural number (n) such that

    p^2 = 12(n)-11. Can you provide a counterexample? Else, can you prove it?

    All prime nos. >3 can be written as 6k+1 or 6K-1.

    So p^2=36k^2+1+12K or -12K. on comparing with 12n-11 or 12(n-1)+1, we get

    12(n-1)=12(3k^2 +or-k) hence n-1 = 3k^2+k or 3k^2-k, where k is > or equal to 1, so it shows, its true for all primes.

  2. Let me rephrase the op. the probability of rolling a 2 with two normal dice is 1/36. The probability of rolling a 3 is 2/36. Can you relabel the dice so that you still get these probabilities and all others using different dice configurations

    How about (1,2,3,4,5,6) and (a,a,a,a,a,a) where a is any +ve integer?

  3. A and B played a game with some amount. They agreed that whoever will lose have to give half his amount to the winner.

    They played 100 games and a result was that A won First game B won next two games A won next three games and so on

    A B B A A A B B B B A A A A A...............

    Who will have graeter amount after the 100th game?

    Whosoever wins the latest game will have more money, so B.

  4. 11, 12, 13, 22, 15, ?, 17, 32, 23, 111, ?

    Fill in the ?'s

    are you sure 111 will follow 23 and nothing is between then?

    as per me,

    16 in 1st blank

    211 in 2nd blank

    My apologies. The last question mark should be before the 111:

    11, 12, 13, 22, 15, ?, 17, 32, 23, ?, 111

    16

    101

    Nope, try again.

    ok then can you tell me this?

    what will come after 111?

    211? or something else?

  5. Look at this pair

    42 24 ( digits of 42 are interchanged i.e =24)

    x 48 x 84 (digits of 48 are interchanged i.e = 84)

    -------- ----------

    2016 2016

    When the digit of multiplicand and multiplier are interchanged then also the result is same.

    How many such pair can you find?

    If you are asking for 2 digit numbers, then

    lets say the numbers are AB and CD, then this property is true if A*C=B*D. eg. 14*82, 24*63 and so on....

  6. 11, 12, 13, 22, 15, ?, 17, 32, 23, 111, ?

    Fill in the ?'s

    are you sure 111 will follow 23 and nothing is between then?

    as per me,

    16 in 1st blank

    211 in 2nd blank

    My apologies. The last question mark should be before the 111:

    11, 12, 13, 22, 15, ?, 17, 32, 23, ?, 111

    16

    101

  7. Suppose n tickets numbered 1-n are in a box, and you draw one of them

    You don't know how many tickets are in the box, but you are asked to estimate how many there are.

    Your ticket has the number p on it.

    What estimate of n has the highest likelihood of being correct?

    It must be p only because then the Probabability of picking out p = 1/p, for n>p, the probability decreases.

  8. I have 3 friends,right?So then, including me, there are 4 people in total.So i can give 4 chocolates each to my friends and keep 4 chocolates with me!

    ^_^

    (This is the very first answer i am giving.I suppose i am the latest member here!)

    Use spoilers buddy! The 'S' option!!

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