WorksheetsModule 2 Exercise 4
Total questions: 10
Worksheet time: 13mins
Find the area to the left of z = -0.15
0.4404
0.5596
0.4405
0.5595
Find the area to the right of z = 1.23 (Answer format: x.xxxx)
(a)
Find the area between z = 0.8 and z = 2.64.
20.77%
81.09%
20.76%
81.1%
What is P(z < -1.35)? (Answer format: x.xxxx)
(a)
What is P(z > 3.49)?
0.02%
2%
0.002%
0.2%
What is P(-3.75 < z < -2.5)? (Answer format: x.xxxx)
(a)
Which normal curve illustrates
P(-1.62 < z < 1.8)?
The mean height of the students at a certain elementary school is 140 cm and the standard deviation is 10 cm. Assuming that the heights are normally distributed, what is the probability that a student will have a height which is less than 155 cm? (Answer format: x.xxxx)
(a)
A public health department closes the beach when the contamination level from a certain pollutant is too high. Suppose research has shown that the index level of the pollutant is normally distributed with a mean of 160 and a standard deviation of 20. What is the probability that the index level of the pollutant exceeds 210?
0.62%
62%
0.062%
6.2%
Suppose that the average number of hours a laptop is used for entertainment purposes is two hours per day. Assume the times for entertainment are normally distributed and the standard deviation for the times is half an hour. What is the probability that a laptop is used for entertainment between 1.8 and 2.75 hours per day?
(Answer format: x.xxxx)
(a)
