P (X ? 150) = P (X > (150-0.5)) = P (X > 149.5)

ii) the probability of no more than 6 absent students in a statistics class.

P (X ? 6) = P (X < (6 + 0.5)) = P (X < 6.5)

iii) the probability that fewer than 24 students understanding continuity correction.

P (X < 24) = P (X < (24-0.5)) = P (X < 23.5)

iv) the probability of exactly 46 marbles.

P (X = 46) = P ((46-0.5) < X < (46 + 0.5)) = P (45.5 < X < 46.5)

Chapter 7

DIRECTIONS: Match the description on the left with the correct word or name on the right. Write the correct letter in the space provided.

Question # 1.

i) ____E____ is the probability 1 - (

A. Margin of Error

ii) __F____ a range of values used to estimate the true B. upper confidence value of a population parameter. limit minus the lower

. confidence limit, divided . By 2.

iii) __B____ maximum error of the estimate C. q = 1 -- p

iv) ____G____ critical value D. Point Estimate

v) ____A__ EE. Confidence level

vi)____D____ is a single value used to approximate a F. Confidence interval population parameter.

vii)____C____ sample proportion of failures in a G. z (/2

sample of size n.

2. According to the text what are the 5 observations needed to determine critical values?

i) Sample proportions approximated by normal distribution

ii) level of significance (?)

iii) two-tailed (?/2) to identify rejection/critical...

Find the critical value corresponding to a 98% of confidence. Use Table A2.
(Make a bell-shaped graph in answering this question)

Z-score

Area

2.05

0.9798

Critical value

0.98

2.06

0.9803

Interpolating gives:

4. Find the margin of error (E) for the 95% confidence interval used to estimate the population proportion.

In a survey of 5400 T.V. viewers, 30% said they watch network news programs.

Given sample size, n = 5400, population proportion, p = 30% = 0.30

The critical value, Zc of 95% confidence level = 1.96

Thus, margin of error E =

5. Use the given confidence interval limits to find the point estimate p and the margin of error E.

(i) (209, 212)

Confidence Interval, CI:, where

: point estimate, E: margin of error,: proportion

Given CI: (209, 212)

(1)

(2)

Adding equations (1) and (2), gives

Subtracting equation (1) from (2), gives

(ii) 2.17( p ( 2.57

Given CI: (2.17, 2.57)

(3)

(4)

Adding equations (3) and (4), gives

Subtracting equation (3) from (4), gives

6. Assume that a sample is used to estimate a population proportion p. Find the margin of error E. that corresponds…