In a survey of a group of men, the heights in the 20-29 age group were normally distributed, with a mean of 66.3 inches and a standard deviation of 4.0 inches. A study participant is randomly selected. Complete parts (a) through (d) below (a) Find the probability that a study participant has a height that is less than 68 inches The probability that the study participant selected at random is less than 68 inches tall is _____

In a certain region, the mean annual salary for electricians is $58,650. Let x be a random variable that represents an electrician's salary.  Assume the standard deviation is $1420.  If a random sample of 50 electricians is selected, what is the probability that the sample mean is greater than $59,000?    A. 0.041   B. 0.403   C. 0.038   D. 0139

An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 150lb and 201lb. The new population of pilots has normally distributed weights with a mean of 155 lb and a standard deviation of 30.4 lb.   a. If a pilot is randomly​ selected, find the probability that his weight is between 150lb and 201 lb.   The probability is approximately ____?

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

the heights of 18-year old men are approximately normally distributed with a mean of U= 68 inches and a standard deviation of O=3. what is the probability that an 18-year-old mean selected at random is less than 65 inches tall.   a .8413 b .1587 c .1389 d .8765

When computing the variance using a sample of size n = 30, we divide the sum of squared deviations by Give your answer as a whole number.

The length of the long-distance calls made by the employees of a certain company are normally distributed with a mean of 6.3 minutes and a standard deviation of 2.5 minutes. Find the probability that a call will last between 5 and 10 minutes. A. .3897     B. .1788.   C. .6290.    D. .6308

Furnace repair bills are normally distributed with a mean of 271 dollars and a standard deviation of 20 dollars. If 64 of these repair bills are randomly selected, find the probability that they have a mean cost between 271 dollars and 273 dollars. Round to four decimal places. A. 0.2881 OB. 0.2119 O C. 0.5517 O D. 0.7881

In a local university, 80% of the students live in the dormitories. A random sample of 64 students is selected for a particular study. The standard deviation of p-bar is   a. 64   b. 0.05   c. 1.6   d. 0.16   e. 0.5

1) The mean and standard deviation of a population are 200 and 20, respectively.The probability of selecting one data value less than 190 is ____ %. (Round answer to the nearest percent (whole number). Do not write the % sign.) 2) A. C. Neilsen reported that children between the ages of 2 and 5 watch an average of 25 hours of television per week. Assume the variable is normally distributed and the standard deviation is 3 hours.If 20 children between the ages of 2 and 5 are randomly selected, the number of children in the sample who watch at least 25.2 hours of television is? Give answer to the nearest whole number, not a percent. 3)  A. C. Neilsen reported that children between the ages of 2 and 5 watch an average of 25 hours of television per week. Assume the variable is normally distributed and the standard deviation is 3 hours.If 20 children between the ages of 2 and 5 are randomly selected, the number of children in the sample who watch at most 22.5 hours of television is? .  Give…