import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);
		double t1;
		int t,x,y;
		x=input.nextInt();y=input.nextInt();
		t=input.nextInt();
		t1=(x*t)*1.0/(y-x);
		System.out.println((int)(x*(t+t1)));;
	}
}

/**************************************************************
	Problem: 1548
	User: admin
	Language: Java
	Result: Accepted
	Time:4317 ms
	Memory:40300 kb
****************************************************************/