Determine class grade using formula

#include <iostream>

using namespace std;

// Determine final class grade using formula:
// Average the two tests and multiply by .4
// Multiply the midterm and final by .3
// Add these together for the final grade.

int main()
{
    float final_grade = 0;
    float test_1 = 0;
    float test_2 = 0;
    float midterm_exam = 0;
    float final_exam = 0;

    cout << "Enter grade for test 1: ";
    cin >> test_1;
    cout << "Enter grade for test 2: ";
    cin >> test_2;
    cout << "Enter grade for midterm exam: ";
    cin >> midterm_exam;
    cout << "Enter grade for final exam: ";
    cin >> final_exam;

    final_grade = (((test_1 + test_2) / 2) * 0.4) +
        (midterm_exam * 0.3) + (final_exam * 0.3);

    cout << "Your final grade is " << final_grade << '\n';

    return 0; // End the program.
}