Topic 1: Events and Their Probabilities

1. When testing a batch of devices, the relative frequency of suitable devices turned out to be 0.9. Find the number of suitable devices, if only 200 devices were tested.

Topic 2: Sequences of Independent Trials (Bernoulli s formula)

2. The company, which has 6 stores in various parts of the city, decided to hold a spring sale of goods of the outgoing season. The probability that the sale will be profitable is 0.6 for each store. What is the likelihood that the sale will be profitable in at least four stores of the company?

Topic 3: Continuous Probability Distributions

3. Find the probability that the standard normally distributed random variable will have values between 2 and 3.