If you dont know the formula just use interpolation. For centigrade, boiling is 100 and freezing is 0. for fahrenheit, boiling is 212 and freezing is 32. so , by interpolation, let x be the unknown..





100 212



X 91



0 32





(100-91) / 100 = (212-X) / (212-32)





the answer is 32.777





^_^

This is how you convert Farenheit to Celsius.



From Farenheit degrees, subtract 32. Then using that figure, divide it by 9, then multiply that answer by 5 for degrees C.



(91 - 32) = 59.



(59/9) x 5 = 32.77 Celsius.





To convert Celsius to Farenheit, you divide degrees C by 5, multiply that by 9, then ADD 32.





The reason this works is this: The boiling point in Farenheit is 212 degrees, the freezing point is 32 degrees.



In Celsius, the boil point is 100 degrees, the freeze point is 0 degrees.



So, by subtracting 32 from Farenheit degrees, the Farenheit range is (212 - 32) = 180 degrees, freeze to boil. Celsius is 100 degrees.



Thus the conversion is (180/100) which when reduced to lowest figure is 9/5 exactly.



Lucky.

32.7778 degree centigrade

I was going to do Let Me Google That For You, but then I realized I'd just be enabling you. Go do your own damn homework. Christ.