how to calculate percentage of four subjects in cpp ?

#include<iostream>

#include<math.h>

 using namespace  std;

int main() 

{

cout<<"****BY DRIODHAN RATHIORE ***"<<endl;

double a,b,c,d,x;

cout<<"enter the  marks of maths ="<<endl;

cin>>a;

cout<<"enter the marks of physics ="<<endl;

cin>>b;

cout<<"enter the marks of chemistry ="<<endl;

cin>>c;

cout<<"enter the marks of English ="<<endl;

cin>>d;

x=(a+b+c+d)*100/400;

cout<<"the total percetange ="<<x;

return 0;

}

#: Welcome once again on sitesbay, today we discuss about how to write code for calculate percentage of marks program in C++. For calculate percentage of marks obtained by student, divide total marks by number of subject ( percentage=total marks / number of subject ).