The workshop has three standby motors operating independently of each other.

The workshop has three standby motors operating independently of each other. For each motor, the probability that it is currently on is 0.2. What is the probability that at least one motor is on at the moment?

The probability that the motor is on: p = 0.2.
The likelihood that the motor is off:
q = 1 – p = 1 – 0.2 = 0.8;
Probability that all three motors are off:
P (3) = q ^ 3 = 0.8 ^ 3 = 0.512.
The probability of the opposite event, in which at least one motor is turned on:
P` (3) = 1 – P (3) = 1 – 0.512 = 0.488.
Answer: The probability that at least one motor is turned on at a given time is 0.488.