C :

#include<stdio.h>
int main()
{
    double x;
    scanf("%lf",&x);
    if(x<=20)
        printf("%.2lf",1.68*x);
    if(x>20)
        printf("%.2lf",1.98*x);
        return 0;
}

C++ :

#include<bits/stdc++.h>
using namespace std;
int main(){
	double q,n;
	cin>>n;
	if(n<=20) q=n*1.68;
	else q=n*1.98;
	cout<<fixed<<setprecision(2)<<q<<endl;
	return 0;
}

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		double a = sc.nextDouble();
		double s;
		if(a<=20){
			s = (double)(a * 1.68);
			System.out.println(String.format("%.2f", s));
		}else if(a > 20){
			s = (double)(a * 1.98);
			System.out.println(String.format("%.2f", s));
		}
		sc.close();
	}

}

Python :

n = float(input())
if n <= 20:
    m = n * 1.68
else:
    m = n * 1.98
print('%.2f' % m)