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2 sums modulo 7 (Posted on 2016-10-05) Difficulty: 2 of 5
Player A rolls m dice, evaluates the sum of all pips Sa, divides it by 7 and writes down the remainder, say rema.
Player B rolls n dice, does the same dividing Sb by 7 and gets remb.
i. Evaluate the probability of both remainders being equal.
ii. How does this probability relate to the numbers m and n?

No Solution Yet Submitted by Ady TZIDON    
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Solution re(2): some computed values Comment 3 of 3 |
(In reply to re: some computed values by Charlie)

Using Sloane's OEIS on the previous results (the unreduced numerators), it seems the formula is:


If we define t = m+n, then the probability is 

(6^t + 6*((-1)^t))/(7 * 6^t)

  Posted by Charlie on 2016-10-05 18:12:19
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