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If the permutations of a, b, c, d, e tak...

If the permutations of a, b, c, d, e taken all together be written dowan in alphabetical order as in dictionary and numbered then the rank of the permutation debac, is

A

90

B

91

C

92

D

93

Text Solution

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The correct Answer is:
D
The letters in alphabatical order are abcde
`a to 4!=24`.
`b to 4!=24" "dc to 3!=6`
`c to 4!=24" "dea to 2!=2`
`da to 3!=6 " becac"to1`
`therefore`The rank of debac=24+24+24+6+6+6+2+1=93
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