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The amount of cereal that can be poured into a small bowl varies with a mean of 1 .5 ounces and a standard deviation of 0 .3 ounces.
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Our large bowl will hold a mean of 2 .5 ounces with a standard deviation of 0 .4 ounces.
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You open a new box of cereal and pour one large and one small bowl.
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How much more cereal do you expect to be in the large bowl? so i'm going to go ahead and make a little table of values here.
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So we have small and we have large.
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And we have a mean and a standard deviation for each.
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So for small our mean is 1 .5, standard deviation is 0 .3.
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Large our mean is 2 .5, standard deviation is 0 .4.
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So for a, we're going to take the difference in our means.
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2 .5 minus 1 .5 means we would expect a difference of 1 ounce.
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Part b, what's the standard deviation of this difference? so standard deviation is going to be the square root of 0 .3 squared plus.
01:07
0 .4 squared and that's going to be 0 .5.
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For part c, if the differences follow a normal model, what's the probability the small bowl contains more serial than the large one? so the probability that x is less than 0...