Sorry man! Here is some code of things I have tried!

Code:
#include <iostream>
#include <cstdlib>

using namespace std;

double ConvertToMPH (int paceInMin, int paceInSec);
double ConvertToMPH (double kph);

int main()
{

  double paceInMin;
  double paceInSec;

  ConvertToMPH (paceInMin, paceInSec);
  cout << "Please enter your pace in minutes: ";
  cin >> paceInMin;
  cout << "Please enter your pace in seconds: ";
  cin >> paceInSec;

  return 0;
}

double ConvertToMPH(int paceInMin, int paceInSec)
{
    return 60/(paceInMin + paceInSec/60.);
}

double ConvertToMPH(double kph)
{
    return kph/1.61;
}


Code:
#include <iostream>
#include <cstdlib>

using namespace std;

double ConvertToMPH (int paceInMin, int paceInSec);
double ConvertToMPH (double kph);

int main()
{

  double paceInMin;
  double paceInSec;

  cout << "Please enter your pace in minutes: ";
  cin >> paceInMin;
  cout << "Please enter your pace in seconds: ";
  cin >> paceInSec;
  ConvertToMPH (paceInMin, paceInSec);

  return 0;
}

double ConvertToMPH(int paceInMin, int paceInSec)
{
    return 60/(paceInMin + paceInSec/60.);
}

double ConvertToMPH(double kph)
{
    return kph/1.61;
}


Code:
#include <iostream>
#include <cstdlib>

using namespace std;

double ConvertToMPH (int paceInMin, int paceInSec);
double ConvertToMPH (double kph);

int main()
{

  double paceInMin;
  double paceInSec;

  
  cout << "Please enter your pace in minutes: ";
  cin >> paceInMin >> ConvertToMPH (paceInMin);
  cout << "Please enter your pace in seconds: ";
  cin >> paceInSec >> ConvertToMPH (paceInSec);

  return 0;
}

double ConvertToMPH(int paceInMin, int paceInSec)
{
    return 60/(paceInMin + paceInSec/60.);
}

double ConvertToMPH(double kph)
{
    return kph/1.61;
}