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# Normal Distribution, Statistical test

1. The net profit of an investment is normally distributed with a mean of \$10,000 and a standard deviation of \$5,000. The probability that the investor's net gain will be at least \$5,000 is _____________.
a) 0.4967
b) 0.8413
c) 0.1859
d) 0.3413

2. A company believes that it controls more than 30% of the total market share for one of its products. To prove this belief, a random sample of 144 purchases of this product are contacted. It is found that 50 of the 144 purchased this company's brand of the product. If a researcher wants to conduct a statistical test for this problem, the test would be _______.
a) an alpha test
b) a one-tailed test
c) a finite population test
d) a two-tailed test

#### Solution Preview

1. The net profit of an investment is normally distributed with a mean of \$10,000 and a standard deviation of \$5,000. The probability that the investor's net gain will be at least \$5,000 is _____________.

a) 0.4967
b) 0.8413
c) 0.1859
d) 0.3413