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Don't have a clue

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Join Date: Dec 2008

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Awebb999

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Don't have a clue

Dec 9th, 2008

23. To convert Fahrenheit ( F ) temperatures to Centigrade ( C ) temperatures people use the formula: (32 degrees F is 0 degrees C, 212 degrees F is 100 degrees C, etc.)
double C,F;

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cin >> F;
	C = ( 5 / 9 ) * ( F - 32 );
	cout << C;

Programmer Pauline noticed a strange problem when she tested the program: the output was always zero no matter what value was for F.
What might fix the problem?
a) C should have been int type
b) The number 32 should have been 32.0
c) The number 9 should have been 9.0
d) F should have been int type
e) 5 / 9 should have been 5 % 9

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Ancient Dragon Ancient Dragon is offline

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Re: Don't have a clue

Dec 9th, 2008

what is the value of 5/9 ? Notice that is integer math, not floating point, so all decimals are lost. Once you understand that, its simple 2nd grade math to figure out the rest of the problem.

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mahlerfive mahlerfive is offline

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Re: Don't have a clue

Dec 9th, 2008

Well if the output is always zero, then either 5/9 is 0 or F-32 is 0. Try and write a small program that just prints the result of 5/9 and one that prints the results of F-32 after the user enters F. That might help you narrow down the problem.