Multiple Choice Identify the
choice that best completes the statement or answers the question.
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1.
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The heights of American men aged 18 to 24 are
approximately normally distributed with mean 68 inches and standard deviation 2.5 inches. Only
about 5% of young men have heights outside the range
a. | 65.5 inches to 70.5 inches | b. | 63 inches to 73 inches | c. | 60.5 inches to
75.5 inches | d. | 58 inches to 78
inches | e. | none of the above |
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2.
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For the density curve shown below, which statement
is true?
a. | The density curve is
symmetric. | b. | The density curve
is skewed right. | c. | The area under the
curve between 0 and 1 is 1. | d. | The density curve
is normal. | e. | None of the above
is correct. |
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3.
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For the density curve shown below, which statement
is true?
a. | The mean and median are
equal. | b. | The mean is greater than the
median. | c. | The mean is less than the
median. | d. | The mean could be either greater than or less than the
median. | e. | None is the above is
correct. |
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4.
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The area under the standard normal curve
corresponding to –0.3<Z<1.6 is
a. | 0.3273 | b. | 0.4713 | c. | 0.5631 | d. | 0.9542 | e. | None of the
above |
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5.
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Suppose that sixteen-ounce bags of chocolate chips
cookies are produced with an actual mean weight of 16.1 ounces and a standard deviation of 0.1 ounce.
The percentage of bags that will contain between 16.0 and 16.1 ounces is
a. | 10 | b. | 16 | c. | 34 | d. | 68 | e. | none of the
above |
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6.
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A company produces packets of soap powder labeled
"Giant Size 32 Ounces." The actual weight of soap powder in a box has a normal distribution
with a mean of 33 oz. and a standard deviation of 0.8 oz. What proportion of packets are underweight
(i.e., weigh less than 32 oz.)?
a. | 0.159 | b. | 0.212 | c. | 0.106 | d. | 0.841 | e. | 0.115 |
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7.
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For the density curve below, what percent of the
observations lie between 0.5 and 1.2?
a. | 25% | b. | 35% | c. | 50% | d. | 68% | e. | 70% |
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8.
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If the heights of 99.7% of American men are between
5'0" and 7'0", what is your estimate of the standard
deviation of the height of American men?
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9.
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Suppose that the distribution of math SAT scores
from your state this year is normally distributed with mean 480 and standard deviation 100 for males,
and mean 440 and standard deviation 120 for females. If someone who scores 780 or higher on math SAT
can be considered a genius, what is the proportion of geniuses among the male SAT
takers?
a. | 26% | b. | 13% | c. | 3% | d. | 1.3% | e. | 0.13% |
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10.
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The average yearly snowfall in Chillyville is
normally distributed with a mean of 55 inches. If the snowfall in Chillyville exceeds 60 inches
in 15% of the years, what is the standard deviation?
a. | 4.81 inches | b. | 5.18 inches | c. | 6.04
inches | d. | 8.93 inches | e. | The standard deviation cannot be computed from the given
information. |
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