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# Letters and Envelopes Problem

There are 5 letters and 5 envelopes and for each letter there is only one right envelope present.In how many ways can one put the letters in the envelopes so that no letter is in the right envelope? I would be really glad to get a hint about its solution.

4 years, 9 months ago

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- 4 years, 8 months ago

ya it is the no. of derangements

- 4 years, 9 months ago

I think the answer is 44.

- 4 years, 8 months ago

Hi; You want the number of derangements. This link covers it all.

- 4 years, 9 months ago