write a letter to your friend inviting him for sister's or brother marriage

'A' writes a letter to his friend 'B' and gives it to his son to post it in a letter box, the reliability of his son being 3/4 . The probability that a letter posted will get delivered is 8/9 .At a later date, 'A' hears from 'B' that the letter has not reached him. Find the probability that the son did not post the letter at all .

'A' writes a letter to his friend 'B' and gives it to his son to post it in a letter box, the reliability of his son being 3/4 . The probability that a letter posted will get delivered is 8/9 .At a later date, 'A' hears from 'B' that the letter has not reached him. Find the probability that the son did not post the letter at all .

Dipesh writes letters to four of his friends. He asks each of them to copy the letter and mail to four different persons with the request that they continue the chain similarly. Assuming that the chain is not broken and that it costs 25 paise to mail one letter, find the total money spent on postage till the 8th set of letters is mailed.

A person writes a letter to four of his friends. He asks each one of them to copy the letter and mail to four different persons with instruction that they move the chain similarly. Assuming that the chain is not broken and that it costs 50 paise to mail one letter. Find the amount spend on the postage when 8th set of letter is mailed.

A person writes a letter to four of his friends. He asks each one of them to copy the letter and mail to four different persons with instruction that they move the chain similarly. Assuming that the chain is not broken and that it costs 50 paise to mail one letter. Find the amount spend on the postage when 8th set of letter is mailed.

A person writes a letter to four of his friends. He asks each one of them to copy the letter and mail to four different persons with instruction that they move the chain similarly. Assuming that the chain is not broken and that it costs 50 paise to mail one letter. Find the amount spend on the postage when 8th set of letter is mailed.

Ajay writes letters to his five friends and addresses the corresponding. The number of ways can the letters by placed in the envelopes so that atleast two of them are in the wrong envelopes is