SOLUTION: Each of the numbers 5 - 15 is written on a sheet of paper. The eleven sheets of paper are placed in a small wicker basket. If two of these eleven sheets of paper are selected from

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Question 1204885: Each of the numbers 5 - 15 is written on a sheet of paper. The eleven sheets of paper are placed in a small wicker basket. If two of these eleven sheets of paper are selected from a basket, without replacement, find the probability that the first number is even and the second number is greater than 10.
Answer by mccravyedwin(407) About Me  (Show Source):
You can put this solution on YOUR website!
If I pick any of these three: 6,8,10, for my even first number, I can
successfully pick any of these five: 11,12,13,14,15, for my second 'greater than
10' number.

That's (3)(5) = 15 ways to pick successfully.

If I pick 12 or 14 for my even first number, I can successfully pick my second
'greater than 10' number 4 ways.  [That is, with 12, I can pick 11,13,14,15, or
with 14, I can pick 11,12,13,15]

That's (2)(4) = 8 more ways to pick successfully.

So there are 15+8=23 ways to pick successfully.

There are (11)(10)=110 ways to pick any first number, then any remaining second
number.

So the desired probability is 23/110 = 0.2090909...

Edwin