Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
In George's closet, there are 13 pairs of pants and 5 shirts. If each outfit consists of one pair of pants and one shirt, then how many outfits does George have?
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Multiplication_priniciple_nPr_nCr.notebook
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April 04, 2017
=
one outfit
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
This example illustrates the Multiplication Principle.
If a task consists of a sequence of choices, and if there are A ways to make the first choice, B ways to make the next choice, C ways to make the third choice, and so on, then there are A(B)(C)(D)... ways to perform the task. From the outfit example.
The TASK is the outfit, A = 13 since there are 13 pairs of pants to choose from, B = 5 since there are 5 shirts to choose from.
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
In George's closet, there are 13 pairs of pants, 5 shirts, and two ties. If each outfit consists of one pair of pants, one shirt, and one tie, then how many outfits does George have? What if we include outfits without ties?
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
Your new employer needs you to choose a password. It consists of 4 alpha­numeric characters. How many passwords are available?
A B C ....Y Z 0 1 2 3 ... 9
10
26
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
A Social Security number consists of 9 numbers ranging from 0 to 9. How many SSNs are there? What if no repeated digits are allowed?
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
Factorial. !
You multiply all naturals less than and equal to the original number. The original number must be a non­negative integer.
Evaluate the following
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
How many 5­letter passwords are there composed of the letters S­O­U­T­H ?
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
On my book shelf I have 7 autobiographies. In how many different ways can I arrange them?
Remember the Multiplication Principle???
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
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Multiplication_priniciple_nPr_nCr.notebook
April 04, 2017
4,5,6,7,8,9,0
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