How to express a term from the Bernoulli formula?

Question

Mathematics

Help me figure out how to solve the problem.
Condition:
"There is a large text message that needs to be sent by Russian Post. We assume that the reliability of message delivery by Russian Post is P. Since the message is initially redundant, it is enough for the recipient to receive N percent of the entire message in order to consider that the message was successfully delivered. Therefore, the sender decided that for reliability it will send the message M in separate equal portions. Into how many parts does the message need to be broken so that it is “successfully delivered” with a predetermined probability?
I understand that you can use the Bernoulli formula . But how can I express k from it (parts of the message will reach k times)?

Answer 1

We consider that the reliability of message delivery by Russian Post is 0 .

Corrected.

Answer 2

In my opinion, this is on the central limit theorem. For large M, the number of arriving chunks will have a normal distribution with expectation P*M and variance P*(1-P)*M. You need to choose M so that the value of the distribution function at the point A=N*M/100 (this is the number of portions you need to get) is no more than 1-S, where S is "a predetermined probability".
This can only be done if P > N/100. Otherwise, the message must be sent in one piece. If P <= N/100 and P < S, then the problem is unsolvable.