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Difficulty: 3 of 5 Latest: N dice (in Probability)
In "5 dice" Andy had five regular dice. Now he has a total of N regular dice. He claims that the odds of rolling exactly M sixes is exactly half as likely as rolling (M-1) sixes. (M < N).

For what values of N is this true?

State the pattern if there is one.

Express M as a function of N.

(No Solution Yet, 0 Comments) Submitted on 2017-05-25 by Larry   
Difficulty: 3 of 5 Bonus: The grass is always greener... (in Paradoxes) Rating: 3.88
You are told there are two envelopes. One contains twice as much money as the other one. You pick one but are allowed to change your mind after picking it. (You are equally likely to pick the one with less money as the one with more money.)

To figure out how much on average the other envelope should contain, one might average x/2 and 2x because one is equally likely to pick one as picking the other. Since this comes out to 5x/4, one might always change his or her mind. But wouldn't this end up with one never making up his or her mind?

(No Solution Yet, 46 Comments) Submitted on 2004-05-06 by Gamer   
Difficulty: 3 of 5Higher Powers of Eleven (in Numbers)
Posted on 2017-05-24 by Brian Smith (No Solution Yet, 1 Comments)
Difficulty: 4 of 5First or second? (in Games) Rating: 3.00
Posted on 2017-05-23 by Ady TZIDON (No Solution Yet, 5 Comments)
Difficulty: 2 of 55 dice (in Probability) Rating: 3.00
Posted on 2017-05-22 by Ady TZIDON (No Solution Yet, 2 Comments)
Difficulty: 4 of 5Add one more circle (in Geometry)
Posted on 2017-05-21 by Brian Smith (No Solution Yet, 5 Comments)
Difficulty: 3 of 5Seven Point Placement (in Shapes) Rating: 4.00
Posted on 2017-05-20 by Brian Smith (No Solution Yet, 1 Comments)
Difficulty: 2 of 5Four balls (in Probability) Rating: 5.00
Posted on 2017-05-19 by Ady TZIDON (No Solution Yet, 21 Comments)
Difficulty: 2 of 5Two sentences about Lady Chatterley (in Logic) Rating: 4.00
Posted on 2017-05-18 by ollie (No Solution Yet, 3 Comments)
Difficulty: 3 of 5Unreliable Witnesses (in Logic) Rating: 3.67
Posted on 2017-05-17 by Charlie (No Solution Yet, 4 Comments)
Difficulty: 3 of 5Hands off! (in Weights and Scales) Rating: 3.00
Posted on 2017-05-16 by Ady TZIDON (No Solution Yet, 3 Comments)
Difficulty: 2 of 5Not every prime qualifies! (in Numbers)
Posted on 2017-05-15 by Ady TZIDON (No Solution Yet, 1 Comments)
Difficulty: 3 of 5Twice blind (in Numbers)
Posted on 2017-05-14 by Ady TZIDON (No Solution Yet, 2 Comments)
Difficulty: 3 of 5How much is "?" ? (in Numbers)
Posted on 2017-05-13 by Ady TZIDON (No Solution Yet, 1 Comments)
Difficulty: 3 of 5Dirichlet sends his regards (in Logic) Rating: 3.00
Posted on 2017-05-12 by Ady TZIDON (No Solution Yet, 4 Comments)
Difficulty: 3 of 5Inder Taneja's discovery (in Numbers)
Posted on 2017-05-11 by Ady TZIDON (No Solution Yet, 4 Comments)

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