Program Code:

#include <iostream>
using namespace std;
int main ( )
{
	//Variables declaration
	double const METRIC_TON = 35273.92;
	double ounce,boxes;
	double weight;
	double numOfBoxex;

	//Prompt and read the input from the keyboard
	cout<<"Enter the weight of a package of breakfast cereal in ounces:";
	cin>>ounce;

	//Calculate the weight in metric tons and display it
	weight = ounce/METRIC_TON;
	cout<<"The weight of the cereal: "<<weight<<endl;
	
	//Calculate the the number of boxes needed to yield one 
	//metric ton of cereal and display it
	numOfBoxex = METRIC_TON/ounce;
	cout<<"The number of boxes of cereal that will hold a ton: "<<numOfBoxex<<endl;
	system("PAUSE");
	return 0;
}

Output:

Enter the weight of a package of breakfast cereal in ounces:100

The weight of the cereal: 0.00283496

The number of boxes of cereal that will hold a ton: 352.739