Question

5, Determine the area under the standard normal curve that lies to the right of ​(a) Z = -0.95 , ​(b) Z=0.53, ​(c)  Z =−0.05, and ​(d) Z =−0.89.

​(a) The area to the right of Z=−0.95 is ____.

​(Round to four decimal places as​ needed.)

​(b) The area to the right of Z=0.53 is _____.

​(Round to four decimal places as​ needed.)

​(c) The area to the right of Z=−0.05 is _____.

​(Round to four decimal places as​ needed.)

​(d) The area to the right of Z=−0.89 is _____..

​(Round to four decimal places as​ needed.)

6,  Determine the area under the standard normal curve that lies between ​(a)  Z =−0.53 and Z=0.53 ​, ​(b)  Z=−2.67 and Z=0​, ​(c)  Z =−0.87 and Z =0.93.

​(a) The area that lies between Z =−0.53 and  Z  =0.53 is ____.

​(Round to four decimal places as​ needed.)

​(b) The area that lies between  Z =−2.67 and  Z =0 is ___.

​(Round to four decimal places as​ needed.)

​(c) The area that lies between  Z =−0.87 and Z =0.93 is _____.

​(Round to four decimal places as​ needed.)

13, A survey was conducted that asked 998 people how many books they had read in the past year. Results indicated that x overbar =13.513.5 books and s =16.1 books. Construct a 95​% confidence interval for the mean number of books people read. Interpret the interval.

(Use ascending order. Round to two decimal places as​ needed.)

A.

If repeated samples are​ taken, 95​% of them will have a sample mean between ___ and ____.

B.

There is 95​% confidence that the population mean number of books read is between ___ and ____.

C.

There is a 95​% probability that the true mean number of books read is between ___ and ___.

18, Steel rods are manufactured with a mean length of 26 centimeter​ (cm). Because of variability in the manufacturing​ process, the lengths of the rods are approximately normally distributed with a standard deviation of 0.06 cm. Complete parts ​(a) to ​(d).

​(a) What proportion of rods has a length less than 25..9 ​cm?

nothing ​(Round to four decimal places as​ needed.)

​(b) Any rods that are shorter than 25.87 cm or longer than 26.13 cm are discarded. What proportion of rods will be​ discarded?

nothing ​(Round to four decimal places as​ needed.)____​(Round to four decimal places as​ needed.)

​(c) Using the results of part ​(b)​, if 5000 rods are manufactured in a​ day, how many should the plant manager expect to​ discard?

____​(Use the answer from part b to find this answer. Round to the nearest integer as​ needed.)

​(d) If an order comes in for 10,000 steel​ rods, how many rods should the plant manager expect to manufacture if the order states that all rods must be between 25.9 cm and 26.1 cm?

___ ​(Round up to the nearest​ integer.)

19, According to a​ study, 59​% of all males between the ages of 18 and 24 live at home. ​ (Unmarried college students living in a dorm are counted as living at​ home.) Suppose that a survey is administered and 163 of 248 respondents indicated that they live at home.​ (a) Use the normal approximation to the binomial to approximate the probability that at least 163 respondents live at home.​ (b) Do the results from part​ (a) contradict the​ study?

​(a) ​P(X≥163​)=___​(Round to four decimal places as​ needed.)

​(b) Does the result from part​ (a) contradict the results of the​ study?

A.

Yes​, because the probability of ​P(X≥163163​) is greater than 0.05 .

B.

Yes​, because the probability of ​P(X≥163​) is less than 0.05

C.

No, because the probability of ​P(X≥163​) is less than 0.05 .

D.

No​, because the probability of ​P(X≥163​) is greater than 0.05.

Answer 1