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tengil
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#1
Report Thread starter 8 years ago
#1
A team of 5 managers is to be selected from a group of 10 managers. 5 from company A, 3 from company B and 2 from company C. In how many ways can this be done of the team must contain at least one manager from every company.

Feels so easy but it doesnt work out, right answer should be 175.
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sciortino
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#2
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That answer doesn't seem very likely to me, unless order is important.
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x_LiNk_x
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#3
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That would take alot of calculations.

Are you sure that answer is correct?
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roxy potter
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#4
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Isn't it

5C1 x 3C1 x 2C1 = 30

multiplied by 7C2 = 21


=630

That's what I'd read from the question anyways. Are you sure the whole question is included above?
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sciortino
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#5
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Agreed.
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ghostwalker
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#6
Report 8 years ago
#6
(Original post by tengil)
Feels so easy but it doesnt work out, right answer should be 175.
Yep, comes to 175.

You need to consider the various cases of how the team of 5 is composed.

For example, one case would be 3 from A, 1 from B and 1 from C.
How many ways can this be done? 5C3 X 3C1 X 2C1 = 60.

There are 4 other cases to consider.
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