sum/4.0为什么会是26.25呢？
public static void main(String[] args) {
int age1=24; int age2=18; int age3=36; int age4=27;
int sum = age1 + age2 + age3 + age4;
double avg = sum/4.0;
System.out.println("年龄总和："+sum);
System.out.println("平均年龄："+avg);
}
