Java随机生成数求平均数之类的

import java.util.Scanner;

public class Test {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        double sum = 0;
        int pass = 0, failed = 0;

        System.out.println("请输入班级人数:");
        int renshu = in.nextInt();

        for (int i = 0; i < renshu; i++) {
            int score = (int) (Math.random() * 61) + 40;

            sum += score;

            if (score >= 60) {
                pass++;
            } else {
                failed++;
            }
        }

        double ave = sum / renshu;

        System.out.println("全班的平均成绩为: " + ave);
        System.out.println("不及格的人数为: " + failed);
        System.out.println("及格的人数为: " + pass);
    }
}

请输入班级人数:
56
全班的平均成绩为: 69.13999999999999
不及格的人数为: 33
及格的人数为: 23