I need help with these questions for my Statistics Worksheet

1.Find the area under the standard normal curve between1.3and themean,P(1.38<z< 0.00).(Round your answer to four decimal places.)

2.Find the area under the standard normal curve betweenz=-1.78andz=1.29,P(-1.78<z<1.29). (Give your answer correct to four decimal places.)

3.Find the area under the standard normal curve betweenz=-2.4andz=1.38,P(-2.4<z<1.38). (Give your answer correct to four decimal places.)

4.Find the area under the standard normal curve betweenz=0.85andz=2.22,P(0.85<z<2.22). (Give your answer correct to four decimal places.)

5.Find the area under the standard normal curve betweenz=-2.67andz=-1.23,P(-2.67<z<-1.23). (Give your answer correct to four decimal places.)

6.Find the two standard scores (z) that correspond to the following. (Enter your answers from smallest to largest. Give your answers correct to two decimal places.)

a)The middle73%of a normal distribution is bounded by them.

and

b)The middle81%of a normal distribution is bounded by them.

and

7.Findz, given the following. (Give your answer correct to two decimal places.)

x=51,=48and=5.1.z = ?

8.Findz, given the following. (Give your answer correct to two decimal places.)

x=239,=215and=12.1.z = ?

9.The weights of ripe watermelons grown at Mr. Smith's farm are normally distributed with a standard deviation of2.6lb. Find the mean weight of Mr. Smith's ripe watermelons if only4%weigh less than11lb. (Give your answer correct to one decimal place.)lb = ?

10."On hold" times for callers to a local cable television company are known to be normally distributed with a standard deviation of1.4minutes. Find the average caller "on hold" time if the company maintains that no more than7%of callers wait more than6.5minutes. (Give your answer correct to two decimal places.)

Minutes = ?

11.IQ scores in a certain population are normally distributed with a mean of101and a standard deviation of14. (Give your answers correct to four decimal places.)

(a) Find the probability that a randomly selected person will have an IQ score between90and115.

(b) Find the probability that a randomly selected person will have an IQ score above90.