Suppose that the time taken for food to spoil using a certain packaging method has an exponential

Question:

Suppose that the time taken for food to spoil using a certain packaging method has an exponential with a mean of 8 days. If a random sample of 100 packets are tested after 10 days, what are the expectation and the standard deviation of the number of packets that will be found with spoiled food? What is the probability that at least 75 of the packets will contain spoiled food?
Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...