HSC Commerce इयत्ता १२ - Tamil Nadu Board of Secondary Education Question Bank Solutions for Business Mathematics and Statistics

Choose the correct alternative:

Using the standard normal table, the sum of the probabilities to the right of z = 2.18 and to the left of z = – 1.75 is

Choose the correct alternative:

The time until the first failure of a brand of inkjet printers is normally distributed with a mean of 1,500 hours and a standard deviation of 200 hours. What proportion of printers fails before 1000 hours?

Choose the correct alternative:

The weights of newborn human babies are normally distributed with a mean of 3.2 kg and a standard deviation of 1.1 kg. What is the probability that a randomly selected newborn baby weight less than 2.0 kg?

Choose the correct alternative:

Monthly expenditure on their credit cards, by credit cardholders from a certain bank, follows a normal distribution with a mean of ₹ 1,295.00 and a standard deviation of ₹ 750.00. What proportion of credit cardholders spend more than ₹ 1,500.00 on their credit cards per month?

Choose the correct alternative:

Let z be a standard normal variable. If the area to the right of z is 0.8413, then the value of z must be:

Choose the correct alternative:

If the area to the left of a value of z (z has a standard normal distribution) is 0.0793, what is the value of z?

Choose the correct alternative:

If P(Z > z) = 0.8508 what is the value of z (z has a standard normal distribution)?

Choose the correct alternative:

If P(Z > z) = 0.5832 what is the value of z (z has a standard normal distribution)?

Choose the correct alternative:

In a binomial distribution, the probability of success is twice as that of failure. Then out of 4 trials, the probability of no success is

A manufacturer of metal pistons finds that on the average, 12% of his pistons are rejected because they are either oversize or undersize. What is the probability that a batch of 10 pistons will contain no more than 2 rejects?

A manufacturer of metal pistons finds that on the average, 12% of his pistons are rejected because they are either oversize or undersize. What is the probability that a batch of 10 pistons will contain at least 2 rejects?

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?

If electricity power failures occur according to a Poisson distribution with an average of 3 failures every twenty weeks, calculate the probability that there will not be more than one failure during a particular week

Vehicles pass through a junction on a busy road at an average rate of 300 per hour. Find the probability that none passes in a given minute

Vehicles pass through a junction on a busy road at an average rate of 300 per hour. What is the expected number passing in two minutes?

Entry to a certain University is determined by a national test. The scores on this test are normally distributed with a mean of 500 and a standard deviation of 100. Raghul wants to be admitted to this university and he knows that he must score better than at least 70% of the students who took the test. Raghul takes the test and scores 585. Will he be admitted to this university?

The time taken to assemble a car in a certain plant is a random variable having a normal distribution of 20 hours and a standard deviation of 2 hours. What is the probability that a car can be assembled at this plant in a period of time. Less than 19.5 hours?

The time taken to assemble a car in a certain plant is a random variable having a normal distribution of 20 hours and a standard deviation of 2 hours. What is the probability that a car can be assembled at this plant in a period of time. Between 20 and 22 hours?

The annual salaries of employees in a large company are approximately normally distributed with a mean of $50,000 and a standard deviation of $20,000. What percent of people earn less than $40,000?

The annual salaries of employees in a large company are approximately normally distributed with a mean of $50,000 and a standard deviation of $20,000. What percent of people earn between $45,000 and $65,000?