SOLUTION: 2. In how many orders can 7 different pictures be hung in a row so that 1 specified picture is
(a) at the center,
(b) at either end?
Show full solution, thank you!
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-> SOLUTION: 2. In how many orders can 7 different pictures be hung in a row so that 1 specified picture is
(a) at the center,
(b) at either end?
Show full solution, thank you!
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Question 1191175: 2. In how many orders can 7 different pictures be hung in a row so that 1 specified picture is
(a) at the center,
(b) at either end?
Show full solution, thank you! Answer by ikleyn(52803) (Show Source):
(a) One of the 7 pictures is fixed; 6 other can be arranged in any order in the remaining 6 positions.
The answer is 6! = 6*5*4*3*2*1 = 720 possible permutations.
(b) 6! + 6! = 720 + 720 = 1440 possible permutations / arrangements.
First 720 arrangements with the specified picture at the left end, and
another 720 arrangements with the specified picture at the right end.
