8. The reading speed of sixth-grade students is approximately normal, with a mean speed of 135 words per minute and a standard deviation of 26 words per minute. Find the probability that a randomly selected sixth-grade student will... a. read at most 100 words per minute. b. read at least 140 words per minute.

Evpte. If the probability of a defective bolt is 0.1, find Ta) the mean (b) the standard deviation for the distribution of defective bolts in a total of 400.

a. The mean of this distribution is b. The standard deviation is c. The probability that the the child will be older than 5 years old?

Citizens use an average of 650 pounds of paper a year. Suppose that the distribution is normal with a population standard deviation of 153.5 pounds.  Suppose you take a random sample of 25 Citizens. What is the probability that the mean pounds of paper used in a year are between 500 and 700 pounds

The average number of pounds of red meat a person consumes each year is 196 with a standard deviation of 22 pounds (Source: American Dietetic Association). If a sample of 50 individuals is randomly selected, find the probability that the mean of the sample will be greater than 200 pounds. OA. 0.0985 OB. 0.9015 OC. 0.8815 O D. 0.7613 C

Cody took his first physics exam and scored an 80. The population mean for this exam is 70, and the standard deviation is 5. What is the probability of selecting a person with a score greater than Cody’s?

All California 5th graders take a standardized test. The mean for the population of 5th graders is 68.9 and the standard deviation for the population is 10. What is the probability of randomly selecting a student who scored   a. ≥ 85? b. less than or equal to 85? c. between 80 & 85? d. between 60 & 85?

The NJ Department of Health has reported the average life span of NJ residents is 81 years. If the standard deviation is σ = 4 years, what is the probability of a person living to at least 92 years of age?

Assume that the number of days from conception to birth is normally distributed with a mean of 258 days and a standard deviation of 10 days. What is the probability that my pregnancy will be between 238 and 278 days? O 75 85 47.5 98 O 95

Assume that the heights of women are normally distributed with a mean of 63.6 inches and a standard deviation of 2.5 inches. If 100 women are randomly selected, find the probability that they have a mean height greater than 63.0 inches. O A. 0.9918 O B. 0.0082 O C. 0.2881 O D. 0.8989 ick to select your answer. DELL