Find the total probability of the event A if X is a normally distributed random variable with expectation x and variance o².

The probability that a machine develops a fault within the first 3 years of use is 0.003. If 40 machines are selected at random, the probability that 38 or more will not develop any faults within the first 3 years of use is ....

You are playing the lottery for 30 days in a row, assuming each day is independent and you know your probability of winning on any given day is p = 0.3 a.)What is the probability that you will win on 5 of the 30 days? b.)What is the expected value of the number of times you will win in 30 days? c.)What is the variance of the number of times you will win in 30 days?

A state government hired a contractor for a road-construction project. The contractor's type, its cost efficienciency, is unknown to the government. There is 2/3 probability of the its construction cost being 3 (billion dollars per lane) and 1/3 probability of the cost being 5. More lanes yield more social benefit in the form of faster travel and fewer accidents. The social value V (measured in billions of dollars) from having N lanes on the highway is: V-15N-N?/2. The government is interested in choose N and writing a contract to maximize the benefit to the state (V) net of the fee paid to the contractor (call it F); G-V-F. Your goal as a government official is to design a pair of contracts to separate the types of contractor. You want the contractor to choose "Contract L: Build N lanes and get paid RL dollars" if its cost type is low cost of $3 (billion dollars per lane) and to choose "Contract H: Build NH lanes and get paid RH dollars" if its cost type is high cost $5 (billion…