In a family of 3 children, what is the probability that there will be exactly 2 girls?

Determine the binomial distribution for which the mean is 4 and variance 3. Also find P(X=15).

Write the conditions for which the poisson distribution is a limiting case of binomial distribution.

Define Standard normal variate.

Hospital records show that of patients suffering from a certain disease 75% die of it. What is the probability that of 6 randomly selected patients, 4 will recover?

In a Poisson distribution 3 P(X = 2) = P(X = 4), then find the parameter of the distribution.

If the mean of the binomial distribution with 9 trial is 6, then find the variance.

If the mean of the binomial distribution is 20 and standard deviation is 4, then find the number of events.

Suppose X is a binomial variate X ~ B (5, p) and P(X = 2) = P(X = 3), then find p.

If 10 coins are tossed, find the probability that exactly 5 heads appears.

Students of a class were given an aptitude test. Marks were found to be normally distributed with mean 60 and S.D. 5. Find the percentage of students who scored more than 60 marks.

In a packet of 50 pens, 10 are defective, 10 pens are selected at random. What is the probability that atleast one is defective.

The random variable X has the normal distribution f(x) = \(C{ e }^{ -\left( \frac { x-100 }{ 50 } \right) ^{ 2 } }\), then find the value of C.

If you buy a lottery ticket in 50 lotteries, in each which your chance of winning a prize is \(\frac { 1 }{ 100 } \). What is the approximate probability that you will win a prize at least once (e-0.5 = 0.6066). 

The probability of the happening of an event X is 0.002 in an experiment. If an experiment is reported 1000 times, find the probability that the event X happens exactly twice? (e^-2 = 0.1353)