HELP!! OG Quantitative Review Question 77

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HELP!! OG Quantitative Review Question 77

by ame84 » Fri Feb 11, 2011 10:25 am
Hi, I'm having trouble with this problem, when solving I get an anwer of 8, I don't know hat I am doing wrong, could someone explain to me why the answer is -40, step by step??
This is the question:

The temperatures in degrees Celsius (C) can be converted to temperatures in degrees Farenheit (F) by the formula
F=9/5C + 32. What is the temperature at which F=C?
Answer = -40
Source: — Problem Solving |

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by maihuna » Fri Feb 11, 2011 10:34 am
C = (9/5)C + 32
=> 5C = 9C + 32*5
=>-4C = 32*5
=> C = -8*5 = -40
Charged up again to beat the beast :)

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by Night reader » Fri Feb 11, 2011 10:42 am
ame84 wrote:Hi, I'm having trouble with this problem, when solving I get an anwer of 8, I don't know hat I am doing wrong, could someone explain to me why the answer is -40, step by step??
This is the question:

The temperatures in degrees Celsius (C) can be converted to temperatures in degrees Farenheit (F) by the formula
F=9/5C + 32. What is the temperature at which F=C?
Answer = -40
first of all F=(9/5)*C + 32 :(
examples: C=0, F=32 --> C=5, F=41
solution: F=C --> 9C/5 +32=C, 9C+160=5C, 4C=-160, C=-40