Grading System program

[Lukecage21]

i needed to create a program that will view student information, choose grades, input grades, calculate grades, check for weighted average, add remarks and generate assessment. the grade components will be 20% assignment, 30% seatwork and 50% quiz. but i'm confused on where should i put the code that will calculate for the grade given the formula. this is my code so far:

 #include<iostream>

using namespace std;

void studentInfo();
void chooseCourse();
void inputGrades();
void calculateGrades();
void checkWeightedEquivalence();
void checkRemarks();
void summary();

struct Student
{
	string name, mailAdd, program;
	int studNum, contactNum, yearLevel;	
	
	string course;
	int prelim, midTerm, finals;
};

Student student;

int main()
{
	studentInfo();
	chooseCourse();

	return 0;
}

void studentInfo()
{	
	cout << "\n Please fill up the following information." << endl;
	
	cout << "\n Name: ";
	cin >> student.name;
	
	cout << " Student No.: ";
	cin >> student.studNum;
	
	cout << " Contact No.: ";
	cin >> student.contactNum;
	
	cout << " Mail Address: ";
	cin >> student.mailAdd;

	cout << " Year Level: ";
	cin >> student.yearLevel;
	
	cout << " Program: ";
	cin >> student.program;
}

void chooseCourse()
{
	system("CLS");
	
	string courses[3] = {"Physics", "DATABASE1", "Math"};
	
	cout << "\n Please choose your course." << endl << endl;
	
	for(int i=0; i<sizeof(courses)/sizeof(courses[0]); i++)
	{
		cout << " [" << i+1 << "] " << courses[i] << endl;
	}
	
	int choice;
	cout << "\n Enter number choice: ";
	cin >> choice;
	
	student.course = courses[choice+1];
}

void inputGrades()
{
	
}

void calculateGrades()
{
	
}

void checkWeightedEquivalence()
{
	
}

void checkRemarks()
{
	
}

[Hengry]

It should be in your calculateGrades() function