C++ Function Definition converts pounds to kilograms

#include <iostream>
using namespace std;
float lbstokg(float);   //declaration
int main()//  w  w  w  .  j  av a 2s.c  o m
{
   float lbs, kgs;
   cout << "\nEnter your weight in pounds: ";
   cin >> lbs;
   kgs = lbstokg(lbs);
   cout << "Your weight in kilograms is " << kgs << endl;
   return 0;
}
// converts pounds to kilograms
float lbstokg(float pounds)
{
   float kilograms =  0.453592 * pounds;
   return kilograms;
}