Q. 55.0( 2 Votes )

# Mark the correct alternative in the following:

The number of different signals which can be given from 6 flags of different colours taking one or more at a time, is

A. 1958

B. 1956

C. 16

D. 64

Answer :

Number of signals which can be given using 1 flag = ^{6}P_{1} = 6

Number of signals which can be given using 2 flag = ^{6}P_{2} = 30

Number of signals which can be given using 3 flag = ^{6}P_{3} = 120

Number of signals which can be given using 4 flag = ^{6}P_{4} = 360

Number of signals which can be given using 5 flag = ^{6}P_{5} = 720

Number of signals which can be given using 6 flag = ^{6}P_{6} = 720

As, the operations are independent, so, the total number of different signals which can be given from 6 flags of different colours taking one or more at a time, is

= 6 + 30 + 120 + 360 + 720 + 720

=__1956__.

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Which of the following are true :

(2 + 3)! = 2! + 3!

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