Please help me to understand P N C grouping by slot method

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by theCodeToGMAT » Thu Nov 28, 2013 2:12 am
Garry, please post one question per thread.

Thanks for cooperation...
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by garry9839 » Thu Nov 28, 2013 9:50 am
A crew of an eight oar boat has to be chosen out of 11men five of whom can row on stroke side only, four
on the bow side only, and the remaining two on either side.How many different selections can be made?

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by garry9839 » Thu Nov 28, 2013 9:51 am
2- 8 man has to be chosen from the 12 man for rowing competition such that 3 of them has always to sit at one side of boat and one at other side .in how many ways we can do this if 4 people has to sit each side?

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by garry9839 » Thu Nov 28, 2013 9:54 am
How would you divide 5 distinct objects in a groups of 2, 2 and 1 ?

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by Mathsbuddy » Thu Nov 28, 2013 9:59 am
There are 3 states and three students representing each state. in how many ways 5 students can be chosen such that at least one student is chosen from each state?

I would look first at probability:
P(1st person being from state A) = 3/9 = 1/3
P(2nd person being from state B) = 3/8
P(3rd person being from state C) = 3/7

So P(A and B and C above) = 1/3 * 3/8 * 3/7 = 3/56

Next, the total number of possibilities = 9 * 8 * 7 * 6 * 5 = 15120

3/56 * 15120 = 810

Does 810 match the correct answer?

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by theCodeToGMAT » Thu Nov 28, 2013 10:11 am
Garry, I meant that you need to post each question in a separate thread, for that you need to create new thread for each question by clicking "Post New Topic" button in each forum. A separate thread will help to avoid any confusion which may creep in while referring solutions or while discussions.

Thanks :)
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