P5719

#include<bits/stdc++.h>
using namespace std;
	int main (){
		int n,k,a1=0,b1=0;
		double yes, no, ans1, ans2;
		cin>>n>>k;
		for(int i=1;i<=n;i++){
			if(i%k==0){
				yes+=i;
				a1++;	
			}
			else {
				no+=i;
				b1++;
			}
		}
		ans1=yes/a1;
		ans2=no/b1;
		cout<<fixed<<setprecision(1)<<ans1<<endl;
		cout<<fixed<<setprecision(1)<<ans2<<endl;
		
	}