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This problem says a european growth mutual fund specializes in stocks from the british isles, continental europe, and scandinavia.
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The fund has over 375 stocks.
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Let x be a random variable that represents the monthly percentage return for this fund.
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Suppose x has a mean of 1 .3 % and a standard deviation of 1 .5%.
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If after 18 months the average monthly percentage return for x is more than 2%, would that tend to shake your confidence in the statement that the mean is equal to 1 .3 %? if this happened, do you think the european stock market might be heating up? and to find our probability that this would occur, we are looking at the probability that the sample mean for these 18 months would be greater than 2%.
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And we weren't told anything about our distribution, so we're going to make the assumption that we're dealing with a normal distribution.
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And that means we'll find our probability using normal cdf in our calculator, which requires us to list four values to get a probability we want.
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Starting with the lower bound and the upper bound that we want the probability between.
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And here we want the probability that our sample mean for these 18 months is greater than 2%, so that means 2 or 2 % would be the lower bound...