Code:#include "stdafx.h" #include <iostream> using namespace std; int multiply() { int one3,two3,three3,four3; int e3,f3, x; cout<<"Input the numerator and denominator of a fraction separated by spaces :"<<endl; cin>>one3; cin>>two3; cout<<"Input the numerator and denominator of a fraction separated by spaces :"<<endl; cin>>three3; cin>>four3; cout<<"Input instruction*_" << endl; e3 = one3*three3; f3 = two3*four3; x=gcd(e3,f3); simplify(e3,f3,x); cout<<"("<< one3 << "/"<< two3 <<") * ("<< three3 <<"/"<< four3 <<") = " << e3 << "/" << f3; cout << "\n"; } int gcd(int x2, int y2) { int i; int gcd2; for (i=1; i<=x2; i++) { if((x2%i==0) && (y2%i==0)) gcd2 = i; } return gcd2; } int simplify(int x2 , int y2 ,int gcd ) { int a; int b; a= x2/gcd; b= y2/gcd; return (a,b); } int main() { multiply(); system ("PAUSE"); }