C :

#include<stdio.h>
int main()
{
	int a,b;
	scanf("%d%d",&a,&b);
	printf("%.1f",(a-1)*2.5+b*1.5);
	return 0;
}

C++ :

#include<iostream>
#include <iomanip>
using namespace std;
int main(){
	int x,y;
	cin>>x>>y;
	cout<<fixed<<setprecision(1)<<((x-1)*2.5+y*1.5)<<endl;
} 

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 b = sc.nextInt();
		double get = (double)((a-1)*2.5+1.5*b);
		System.out.println( String.format("%.1f", get));
		
	}
	public static void printArr(int [] a){
		for (int i = 0 ;i<= a.length - 1 ;i++) {
			System.out.print( a[i] + " ");
		}
	}
}

Python :

s = input().split()
x = int(s[0])
y = int(s[1])
a = x - 1
print("%.1f" % (a * 2.5 + y * 1.5))