Refer to Exercise 21. Is it possible for the probability that both gauges fail to be greater than 0.01? Explain.

Exercise 21: Nuclear power plants have redundant components in important systems to reduce the chance of catastrophic failure. Assume that a plant has two gauges to measure the level of coolant in the reactor core and that each gauge has probability 0.01 of failing. Assume that one potential cause of gauge failure is that the electric cables leading from the core to the control room where the gauges are located may bum up in a fire. Someone wishes to estimate the probability that both gauges fail, and makes the following calculation:

P (both gauge fail) = P(first guage fails) × P (Second guage fails)

= (0.01)(0.01)

= 0.0001

a. What assumption is being made in this calculation?

b. Explain why this assumption is probably not justified in the present case.

c. Is the probability of 0.0001 likely to be too high or too low? Explain.

Answer :

Step 1 of 2 :

Given,

From the given exercise the probability of first gauge fail is 0.01 and the probability of second gauge fails is 0.01

The claim is to check that the probability that both gauges fail to be greater than 0.01.