An automobile battery manufacturer claims their batteries have an average life of 5.2 years with a standard deviation of 0.6 years.

Assuming battery life is normally distributed, the probability a random sample of 16 batteries has an average life greater than 5.5 years is

A sample mean distribution with sample sizes of 16 finds a sample mean value of 32 and sample standard deviation of 12. What is the probability a random sample will be less than 30?

A sample of size 36 is drawn from a population in which the proportion of members with the characteristic of interest is p = 0.30. What is the probability that the sample proportion will be between 0.28 and 0.34?

A sample of size 50 is drawn from a population in which the proportion of members with the characteristic of interest is p = 0.25. What is the probability that the sample proportion will be greater than 0.58?

A sample mean distribution with sample sizes of 225 are drawn from a population with a mean of 42 and standard deviation of 9. What is the probability a sample mean will be less than 41?

species of fish has a normally distributed population with a mean weight of 6 pounds with a standard deviation of 0.75 pounds. What is the standard deviation of the sample means of size 25 taken from this population of fish?

A sample of size 25 is drawn from a population in which the proportion of members with the characteristic of interest is p = 0.6. What is the probability that the sample proportion will be less than 0.58?

A sample mean distribution with sample sizes of 121 are drawn from a population with a mean of 80 and standard deviation of 22. What is the probability a sample mean will be between 77 and 81?

A random sample of 25 high-lift buckets of gravel finds their mean weight is 2040 pounds with a standard deviation of 120 pounds. What is the probability another random sample of 25 high-lift buckets will have a mean of at least 2100 pounds?

A sample mean distribution with sample of size 15 has a mean of 26 and standard deviation of 2.5.

The probability a sample mean of this size will be between 25 and 26.5 is

Question Blank

The population standard deviation of a random variable is 8. Given that the population is normally distributed, what is the standard deviation of the of sample means of size 16 for this random variable?

A marketing company estimates about 35% of the population is interested in purchasing a mattress within the next year.

The probability a random sample of 81 individuals will have more than 40% of it interested in purchasing a mattress within the next year is

A sample mean distribution with sample sizes of 100 are drawn from a population with a mean of 80 and standard deviation of 15. What is the probability a sample mean will be greater than 81.8 ?