Implement the following integer methods:

a)method Celsius return the Celsius equivalent of a Fahrenheit temperature, using the calculation
Celsius = 5.0/9.0*(Fahrenheit -32);

b) method Fahrenheit returns the Fahrenheit equivalent of a Celsius temperature, using the calculation
Fahrenheit = 9.0/5.0*(Celsius +32);

c)use the method from part (a) and (b) to write an application the enables the user either to enter a Fahrenheit temperature and display the Celsius equivalent or enter a Celsius temperature and display the Fahrenheit equivalent

This is the software program and the problem I am having is that I cannot get the program to give me the correct answer!

// Exercise 6.22: Convert. java
// Use a method to write an application to enable the user
// Either to enter a Fahrenheit and Celsius equivalent
// Or enter a Celsius temperature and display the Fahrenheit
// program use scanner class
import java. util. Scanner;

public class Convert
{
// convert temperatures
public void ConvertTemperature()
{
Scanner input = new Scanner( System. in );
double convert;
int selection;
double temp;
double converts;

do
{
// print and prompt for input from user
System. out. println("");
System. out. println( "Main Menu" );
System. out. println( "Enter 1 for Fahrenheit to Celsius equivalent " );
System. out. println( "Enter 2 for Celsius to Fahrenheit equivalent" );
System. out. println( "3 to Exit\n " );
System. out. print( "Selection: " );
selection = input. nextInt();

// converts celsius to fahrenheit
// converts fahrenheit to celsius

switch ( selection )
{
case 1:
System. out. println("Enter fahrenheit temperature: " );
temp = input. nextInt();
convert = celsius( temp );
System. out. printf("%f degrees F = %f degrees C\n",temp, convert );
break;

case 2:
System. out. println("Enter celsius temperature: " );
temp = input. nextInt();
converts = fahrenheit( temp );
System. out. printf("%f degrees C = %f degrees F\n", temp, converts );
break;

case 3:
break;

default:
System. out. println( "Invalid selection" );

} // end of switch
} while( selection != 3);
} // end of convertTemperatures
public static double fahrenheit(double celsius)
{
double fahrenheit;
fahrenheit = 9 / 5 * (celsius + 32);

return fahrenheit;
}

public static double celsius(double fahrenheit)
{
double celsius;
celsius = 5 / 9 * (fahrenheit - 32);

return celsius;
}

}