/*
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    While•Ά ‡Œv‚Ζ•½‹Ο  While_02_goukei
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*/
import java.io.*;
import java.text.*;
class While_02_goukei {
	public static void main(String[] args ) throws Exception{
		int kazu;
		int goukei=0;
		int kensu=0;
		double heikin;
		
		DecimalFormat fm=new DecimalFormat("0.00");
		
		BufferedReader inp=new BufferedReader
			(new InputStreamReader(System.in));
		String keybd;
		
		System.out.print("”‚π“ό‚κ‚Δ‰Ί‚³‚’i‚O‚ŏI—Ήj\n");
		System.out.print("-->");
		keybd=inp.readLine();
		kazu=Integer.parseInt(keybd);
		
		while ( kazu != 0 ) {
			goukei+=kazu;
			kensu++;
			
			System.out.print("-->");
			keybd=inp.readLine();
			kazu=Integer.parseInt(keybd);
		}
		System.out.print("‡Œv"+goukei+"\n");
		System.out.print("Œ”"+kensu+"\n");
		
		heikin=(double)goukei/kensu;
		System.out.print("•½‹Ο"+fm.format(heikin)+"\n");
	}
}