for part a, mean is 14.5 million
for part b… i found standard deviation… under root of {[(15-14.5)^2 + (14-14.5)^2] / 2} which was .5
so for prob of 14.125 million … i subtracted 14.125- 14.5 = -0.375 million and divided by standard deviation getting (-0.375/.5 = -0.75) … so i am -0.75 below mean… i looked tht up in cumulative probability table (z table) and found it to be 22.66 percent…
but in the book… they are saying its 12. 5 percent like so… (14.125-14) / (15-14) … which makes sense…
but my way also makes sense to me… but the answer isnt the same… what am i doing wrong…
The probability distribution here is just a rectangle, not a bell-shaped curve. 
For the continuous uniform, the variance is (1,000,0002)/12.
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umm ok i guess the z table cant be used cuz thts only for continuous prob… which makes it a bell shaped… but i dont get how youre getting tht variance… appreciate it if u could shed some more light on tht…thanks bread…
as bread pointed out, the problem asks you to use the uniform continuous distribution, not the normal distribution. the variance formula is a result you can find in any elementary probability book. (it should not be difficult to derive by using the definition of the uniform pdf and the fact that variance is the second central moment. ) if X is uniformly continuously distributed on (a, b),
its variance is (b - a)2 / 12
since the sales are uniformly distributed on (14 million, 15 million), its variance is
(15 million - 14 million)2 / 12, which is the answer bread gave above.
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thanks you guys… this really helped…