Problem 9.

R rifles stand in the pyramid. L of them have optical sight. The probability that the shooter firing a rifle with an optical sight will hit the target is equal to p₁. The probability that the shooter firing a rifle without an optical sight will hit the target is equal to p₂. Find the probability that the shooter will hit the target firing a rifle that is chosen at random.

Value of the parameters should be calculated according to the following formulas

( where B is number of variant)

Problem 10

The plant use electric motors, supplied by 3 plants. There are electric motors in an amount of , , units, that are able to work without failure until the end of the warranty period with the next probability: , , . A worker at random selects one electric motor and mounts it to the car. Find the probability that mounted electric motor that works without failure until the end of the period is made on

1. the first,

2. second

3. third plant.

Value of the parameters should calculate according to the following formulas:

( where B is number of variant)