About 20% of Americans are bilingual. A ramdom sample of 7 americans is drawn a. find the probability that at most 3 are bilingual b. find the expected value and standard deviation.

Solve the problem.Assume that mountain lions' weights are normally distributed with a mean of 62.6 kilograms and a standard deviation of 2.6 kilograms. If 70 mountain lions are randomly selected, find the probability that they have a mean weight between 61.9 kilograms and 62.8 pounds.

65% of the dogs in the competition run at the Excellent or Master’s level. Suppose 20 dogs are randomly selected.  Use the binomial probability table to find the probability. A. Fewer than 14 dogs are at the Excellent or Master’s level. B.Exactly 11 dogs are at the Excellent or Master’s level.  C.Give the mean and standard deviation if 300 dogs are selected with 65% at the Excellent or Master’s level.

An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 120 lb and 181 lb. The new population of pilots has normally distributed weights with a mean of 129 lb and a standard deviation of 31.8 lb. a. If a pilot is randomly​ selected, find the probability that his weight is betwee 140 lb and 191 lb.   The probability is approximately .5776 b. I 34 different pilots are randomly​ selected, find the probability that their mean weight is between 140 lb and 191 lb.   The probability is approximately ____

Airline passengers arrive randomly and independently at the passenger-screening facility at a major international airport. The mean arrival rate is 7 passengers per minute. a. Compute the probability of no arrivals in a one-minute period (to 6 decimals).

Driving home from school, you always seem to hit every light. You calculate the odds of making it through a light to be 0.2. a. How many lights can you expect to hit before making it through one? b. With what standard deviation? c. What is the probability of the 3rd light being the first one that is green?

. Assume that 10% of people are left-handed. Condsider a random sample of 5 people. What is the probability that all of them are left-handed. Please answer quickly

The average salary for teachers is $50,000 with a std. deviation of $5,000. Find probability of randomly selecting a teacher that makes: between $35,000 and $45,000| b more than $45,000 per year a 0.167, 0.881 0.147 , 0.811 0.157, 0.841 0.137, 0.861

Suppose that you are studying the number of vehicles owned by a US household. You find that the average is 1.9 vehicles per household with a standard deviation of 2.8 vehicles per household. What is the most likely shape for the population described above?  Find the probability that 40 randomly selected households have an AVERAGE number of vehicles greater than 2.5.

Let the random variable x represent the number of girls in a family of 3 children. Construct a table describing the probability distribution, then find the mean and SD. Is it unusual for a family of 3 children to consist of 3 girls