Jay black
2 years ago
10
1. According to The Yankee Group, 53% of all cable households rate cable companies as good or excellent in quality transmission. Sixty percent of all cable households rate cable companies as good or excellent in having professional personnel. Suppose 300 cable households are randomly contacted.
(a) What is the probability that more than 175 cable households rate cable companies as good or excellent in quality transmission?
(b) What is the probability that between 164 and 168 (inclusive) cable households rate cable companies as good or excellent in quality transmission?
(c) What is the probability that between 153 and 170 (inclusive) cable households rate cable companies as good or excellent in having professional personnel?
(d) What is the probability that fewer than 201 cable households rate cable companies as good or excellent in having professional personnel?
2. According to the government of Manitoba, the average hourly wages are as follows: Alberta: $22.02, Ontario: $20.18, British Columbia: $20.05.
a. Suppose 36 workers are selected randomly from across Alberta and asked what their hourly wage is. What is the probability that the sample average will be between $21 and $22?
b. Suppose 34 manufacturing workers are selected randomly from across Ontario. What is the probability that the sample average will exceed $23?
c. Suppose 47 manufacturing workers are selected randomly from across British Columbia. What is the probability that the sample average will be less than $18.60? Assume that in all three provinces, the standard deviation of hourly wages is $3.
3. A study about strategies for competing in the global marketplace states that 52% of the respondents agreed that companies need to make direct investments in foreign countries. It also states that about 70% of those responding agree that it is attractive to have a joint venture to increase global competitiveness. Suppose CEOs of 95 manufacturing companies are randomly contacted about global strategies.
(a) What is the probability that between 45 and 51 (inclusive) CEOs agree that companies should make direct investments in foreign countries?
(b) What is the probability that more than 57 CEOs agree with that assertion?
(c) What is the probability that fewer than 59 CEOs agree that it is attractive to have a joint venture to increase global competitiveness?
(d) What is the probability that between 53 and 61 (inclusive) CEOs agree with that assertion?
