SOLUTION: Data on investments in the high-tech industry by venture capitalists are compiled by VentureOne Corporation and published in America’s Network Telecom Investor Supplement. A rand

Algebra.Com
Question 923201: Data on investments in the high-tech industry by venture capitalists
are compiled by VentureOne Corporation and published in America’s Network Telecom Investor
Supplement. A random sample of 18 venture-capital investments in the fiber optics business sector
yielded the following data, in millions of dollars.
5.60 6.27 5.96 10.51 2.04 5.48 5.74 5.58 4.13
8.63 5.95 6.67 4.21 7.71 9.21 4.98 8.64 6.66
(a) Determine a 90% confidence interval for the mean amount, µ, of all venture-capital investments in
the fiber optics business sector, and interpret your answer. Assume that the population standard
deviation is $2.04 million. (The sum of the data is $113.97 million)
(b) Determine a 50% confidence interval for the mean amount, µ, of all venture-capital investments in
the fiber optics business sector, and interpret your answer.
(c) Determine the minimum sample size required to have a margin of error of $0.05 million with a 90%
confidence interval.

Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
18 venture-capital investments in the fiber optics business sector
Mean = 6.33 , standard deviation = 2.04 (also Pop sd)
90% confidence interval
ME = 1.74 (2.04/sqrt(18))
CI: 6.33-ME < u < 6.33 + ME
.....
50% confidence interval ...
ME = .689 (2.04/sqrt(18))
CI: 6.33-ME < u < 6.33 + ME
.......
minimum sample size required to have a margin of error of $0.05 million with a 90% confidence interval.
.05 = 1.645((2.04/sqrt(n))
n =
.......
 
DF Probability, p 2-tailed
0.1 0.05 0.01 0.001
1 6.31 12.71 63.66 636.62
2 2.92 4.3 9.93 31.6
3 2.35 3.18 5.84 12.92
4 2.13 2.78 4.6 8.61
5 2.02 2.57 4.03 6.87
6 1.94 2.45 3.71 5.96
7 1.89 2.37 3.5 5.41
8 1.86 2.31 3.36 5.04
9 1.83 2.26 3.25 4.78
10 1.81 2.23 3.17 4.59
11 1.8 2.2 3.11 4.44
12 1.78 2.18 3.06 4.32
13 1.77 2.16 3.01 4.22
14 1.76 2.14 2.98 4.14
15 1.75 2.13 2.95 4.07
16 1.75 2.12 2.92 4.02
17 2.11 2.9 3.97
18 1.73 2.1 2.88 3.92

RELATED QUESTIONS

The following excerpt is from an article in The New York Times in July 1999.† While... (answered by ikleyn)
The following excerpt is from an article in The New York Times in July 1999.† While... (answered by ikleyn)
Question 1 The Sales manager at Hybrid Industries a high tech farming agency claims that... (answered by Boreal)
Statistician Jim Albert compiled data about every pitch thrown by 20 starting pitchers... (answered by Boreal)
Lilly collects data on a sample of 40 high school students to evaluate whether the... (answered by ikleyn)
Seventy-six percent of the shareholders in a service corporation are woman. if the... (answered by josgarithmetic)
A person made two investments, and the percentage return per year on each was the same.... (answered by richwmiller)
the pollution count for big city in a particular day is 575. Assume this pollution is... (answered by Fombitz)
Each year, ratings are compiled concerning the performance of new cars during the first... (answered by ikleyn)