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Difficult Math Question #12

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Difficult Math Question #12

by 800guy » Mon Sep 11, 2006 7:44 pm
OA after a few people answer..

The average of temperatures at noontime from Monday to Friday is 50; the lowest one is 45, what is the possible maximum range of the temperatures?

A) 20

B) 25

C) 40

D) 45

E) 75
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by jayofbay » Tue Sep 12, 2006 12:05 am
5x50 = 45x4 + x
x = 70
Hence range is 70-45=25

Answer is B
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by 800guy » Wed Sep 13, 2006 7:12 pm
OA:

The answer 25 doesn't refer to a temperature, but rather to a range of temperatures.

The average of the 5 temps is: (a + b + c + d + e) / 5 = 50
One of these temps is 45: (a + b + c + d + 45) / 5 = 50
Solving for the variables: a + b + c + d = 205
In order to find the greatest range of temps, we minimize all temps but one. Remember, though, that 45 is the lowest temp possible, so: 45 + 45 + 45 + d = 205
Solving for the variable: d = 70
70 - 45 = 25
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