C :

#include<stdio.h>
int main()
{
	int a,b,c,d;
	scanf("%d",&a);
	b=a%10;
	c=a/100;
	d=a/10-c*10;
	printf("%.2f",(c+d)*1.0/(b+d));
	return 0;
}

C++ :

#include <iostream>
#include <iomanip>
using namespace std;

int main(){
	int n,g,s,b;
	cin>>n;
	b = n / 100;
	s = n / 10 % 10;
	g = n % 10;
	
	cout<<fixed<<setprecision(2)<<(b+s)*1.0/(s+g);
}

Java :

import java.util.Scanner;

public class Main {
	 
    /**
     * @param args
     */
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = sc.nextInt();
		int g = a%10;
		int s = a/10%10;
		int b = a/100;
		double sum = (double)(b+s)/(s+g);
		System.out.println(String.format("%.2f", sum));
		
	}
	public static void printArr(int [] a){
		for (int i = 0 ;i<= a.length - 1 ;i++) {
			System.out.print( a[i] + " ");
		}
	}
}

Python :

n = int(input())
b = n // 100 % 10
s = n // 10 % 10
g = n // 1 % 10
x = b + s
y = s + g
print("%.2f" % (x / y))