Problem of the week

 

Five letters are written to five different persons and their addresses are on 5 envelopes. Find in now many ways letters can be placed in envelopes so that no letter is placed in the correct envelope.

 

Solution:

For five envelopes A  B C D and E taking b, we get

 

a6

 

Similarly if c is sent to A there will be 11 ways. Hence total  - 4x11 = 44 ways.

 

Correct solution received from:

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