A committee with 3 members is to be chosen randomly from 5 boys and 7 girls and count the number of girls on the committee. a) Identify the two groups. b) In words, describe the random variable X. c) List the values of the random variable X takes on. d) What is the expected number of girls on the committee? e) Determine the standard deviation of the number of girls in the committee.

A random variable follows the normal probability distribution with a mean of 100 and a standard deviation of 10. determine the probability for a random selected value from this population.  a) what is the probability that the value is less than 90?  b) what is the probability that the value is less than 95?  c) what is the probability that the value is more than 130?  d) what is the probability that the value is more than 85?  Please help me! Thank You!

Assume that different groups of couples use a particular method of gender selection and each couple gives birth to one baby. This method is designed to increase the likelihood that each baby will be a girl, but assume that the method has no effect, so the probability of a girl is 0.5. Assume that the groups consist of 43 couples. Complete parts (a) through (c) below. a. Find the mean and the standard deviation for the numbers of girls in groups of 43 births. The value of the mean is = (Type an integer or a decimal. Do not round.) The value of the standard deviation is o = (Round to one decimal place as needed.) b. Use the range rule of thumb to find the values separating results that are significantly low or significantly high. Values of girls or fewer are significantly low. (Round to one decimal place as needed.) Values of girls or greater are significantly high. (Round to one decimal place as needed.) c. Is the result of 41 girls a result that is significantly high? What does it…

Assume that different groups of couples use a particular method of gender selection and each couple gives birth to one baby. This method is designed to increase the likelihood that each baby will be a girl, but assume that the method has no effect, so the probability of a girl is 0.5. Assume that the groups consist of 44 couples. Complete parts (a) through (c) below. a. Find the mean and the standard deviation for the numbers of girls in groups of 44 births. The value of the mean is (Type an integer or a decimal. Do not round.) The value of the standard deviation is o = (Round to one decimal place as needed.) b. Use the range rule of thumb to find the values separating results that are significantly low or significantly high. Values of girls or fewer are significantly low. (Round to one decimal place as needed.) Values of girls or greater are significantly high. (Round to one decimal place as needed.) c. Is the result of 35 girls a result that is significantly high? What does it…

Surgery has a success rate of 80% . suppose that the surgery is performed and 3 patients . A)what is the probability the surgery is successful in exactly 2 patients?  B)what is the probability of getting success in less than 2 patients? C)on average, how many surgeries we expect to be successful?  D)what is the standard deviation of numbers of successful surgeries?