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标题: Reading 8: Probability Concepts-LOS o, (Part 2)习题精选 [打印本页]
作者: bmaggie    时间: 2010-4-12 15:30     标题: [2010]Session 2:-Reading 8: Probability Concepts-LOS o, (Part 2)习题精选

Session 2: Quantitative Methods: Basic Concepts
Reading 8: Probability Concepts

LOS o, (Part 2): Solve counting problems using the factorial, combination, and permutation notations.

 

 

 

A supervisor is evaluating ten subordinates for their annual performance reviews. According to a new corporate policy, for every ten employees, two must be evaluated as “exceeds expectations,” seven as “meets expectations,” and one as “does not meet expectations.” How many different ways is it possible for the supervisor to assign these ratings?

A)
 360.
B)
 10,080.
C)
 5,040.

作者: bmaggie    时间: 2010-4-12 15:30

A supervisor is evaluating ten subordinates for their annual performance reviews. According to a new corporate policy, for every ten employees, two must be evaluated as “exceeds expectations,” seven as “meets expectations,” and one as “does not meet expectations.” How many different ways is it possible for the supervisor to assign these ratings?

A)
 360.
B)
 10,080.
C)
 5,040.


The number of different ways to assign these labels is:


作者: bmaggie    时间: 2010-4-12 15:31

A firm wants to select a team of five from a group of ten employees. How many ways can the firm compose the team of five?

A)
 120.
B)
 25.
C)
 252.

作者: bmaggie    时间: 2010-4-12 15:31

A firm wants to select a team of five from a group of ten employees. How many ways can the firm compose the team of five?

A)
 120.
B)
 25.
C)
 252.


This is a labeling problem where there are only two labels: chosen and not chosen. Thus, the combination formula applies: 10! / (5! × 5!) = 3,628,800 / (120 × 120) = 252.

With a TI calculator: 10 [2nd][nCr] 5 = 252.
作者: bmaggie    时间: 2010-4-12 15:31

A portfolio manager wants to eliminate four stocks from a portfolio that consists of six stocks. How many ways can the four stocks be sold when the order of the sales is important?

A)
 180.
B)
 24.
C)
 360.

作者: bmaggie    时间: 2010-4-12 15:31

A portfolio manager wants to eliminate four stocks from a portfolio that consists of six stocks. How many ways can the four stocks be sold when the order of the sales is important?

A)
 180.
B)
 24.
C)
 360.


This is a choose four from six problem where order is important. Thus, it requires the permutation formula: n! / (n ? r)! = 6! / (6 ? 4)! = 360.

With TI calculator: 6 [2nd][nPr] 4 = 360.

作者: zaestau    时间: 2010-4-26 23:36

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