Two jokers are added to a $52$ card deck and the entire stack of $54$ cards is shuffled randomly. What is the expected number of cards that will be strictly between the two jokers?

  52/3.

Step-by-step explanation:

There are (54·53)/2 = 1431 ways the 2 jokers can be placed in the 54-card deck. We can consider those to see how the number of cards between them might work out.

Suppose we let J represent a joker, and - represent any other card. The numbers of interest can be found as follows:

For jokers: JJ---... there are 0 cards between. This will be the case also for ...

  -JJ---...

  --JJ---...

and so on, down to ...

 ...---JJ

The first of these adjacent jokers can be in any of 53 positions. So, the probability of 0 cards between is 53/1431.

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For jokers: J-J---..., there is 1 card between. The first of these jokers can be in any of 52 positions, so the probability of 1 card between is 52/1431.

__

Continuing in like fashion, we find the probability of n cards between is (53-n)/1431. So, the expected number of cards between is ...

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb

step-by-step explanation:

3024 rhe base is what up in worry about