Class to convert between Celcius, Fahrenheit and Kelvin temperatures.
Set one temperature and automatically get the other two.
This class makes use of properties. See the code snippet for details.
A short main program is added to exercise the Temperature class by printing a conversion table between celsius and fahrenheit.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Console_Temperature
    class Temperature
        private const double cAbsTempC = 273.15;//absolute temperature in Celcius
        private const double cAbsTempF = 459.67;//absolute temperature in Fahrenheit

        private double _Kelvin = 0.0; 

        public Temperature(){}

        public Temperature(double kelvintemp)
            _Kelvin = kelvintemp;

        public double Celcius 
            get { return _Kelvin - cAbsTempC; }
            set { _Kelvin = value + cAbsTempC; }

        public double Fahrenheit
            get { return _Kelvin*9/5 - cAbsTempF; }
            set { _Kelvin = (value + cAbsTempC)*5/9; }

        public double Kelvin
            get { return _Kelvin; }
            set { _Kelvin = value; }

  class Program
        static void Main(string[] args)
            // print a table from 0 to 10 degrees C,
            // with the conversion to Fahrenheit degrees,
            // using the Temperature class
            Temperature temp = new Temperature();
            Console.WriteLine("Celcius \t Fahrenheit");
            for (int i = 0; i <= 10; i++)
                temp.Celcius = i;
                Console.WriteLine("{0}  \t  {1}", temp.Celcius, temp.Fahrenheit);

You are right MosaicFuneral. If we can avoid division we must!
I left 5/9 and 9/5 in because it is clearer to understand. I a real situation I would also use 1.8 and 0.55555.
Btw. the absolute temp constants are in a way not correct either!
Real absolute temps are negative, but here the calculations done are correct.

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