SOLUTION: The weather in Rochester in December is fairly constant. Records indicate that the low temperature for each day of the month tend to have a uniform distribution over the interval 1

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Question 1192722: The weather in Rochester in December is fairly constant. Records indicate that the low temperature for each day of the month tend to have a uniform distribution over the interval 15 to 35 F. A business man arrives on a randomly selected day in December.
(a) What is the probability that the temperature will be above 17?
answer:
0.05
(b) What is the probability that the temperature will be between 19 and 32?
answer:
(c) What is the expected temperature?
answer:

Answer by ikleyn(52802) About Me  (Show Source):
You can put this solution on YOUR website!
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The weather in Rochester in December is fairly constant. Records indicate that the low temperature for each day
of the month tend to have a uniform distribution over the interval 15 to 35 F.
A business man arrives on a randomly selected day in December.
(a) What is the probability that the temperature will be above 17?
answer:
0.05
(b) What is the probability that the temperature will be between 19 and 32?
answer:
(c) What is the expected temperature?
answer:
~~~~~~~~~~~~~~~~~~~~~

(a)  The base interval for comparison is  | 35 - 15 | = 20 degrees of F.

     Working interval is  | 35 - 17 | = 18 degrees of F.


     The probability under the problem' question is the ratio of the working interval to the base interval


         P = 18%2F20 = 9%2F10 = 0.9 = 90%.    ANSWER.        The answer 0.05 in your post is wrong.




(b)  The base interval for comparison is  | 35 - 15 | = 20 degrees of F.

     Working interval is  | 32 - 19 | = 13 degrees of F.


     The probability under the problem' question is the ratio of the working interval to the base interval


         P = 13%2F20 = 0.65 = 65%.    ANSWER.  




(c)  The expected value of the uniform distribution U(a,b) is the same as its mean  %28a+%2B+b%29+%2F+2. 

     Note, that this is precisely the midpoint of the interval [a,b] .


     In this problem, the expected temperature is  %2815+%2B+35%29%2F2 = 50%2F2 = 25 degrees of F.

Solved.