#include<iostream>

 #include<stdio.h>

 #include<algorithm>

 #include<iomanip>

 #include<cmath>

 #include<cstring>

 #include<vector>

 #define ll __int64

 #define pi acos(-1.0)

 #define MAX 1003

 using namespace std;

 struct point

 {

     double c,b,r;

 }p[MAX][MAX];

 double dp[MAX][MAX];

 int main(){

     int n,m,i,j;

     while(scanf("%d%d",&n,&m)!=EOF){

         for(i=;i<=n;i++)

             for(j=;j<=m;j++)

                 scanf("%lf%lf%lf",&p[i][j].c,&p[i][j].r,&p[i][j].b);

         dp[n][m]=0.0;

         for(i=n;i>=;i--)

         for(j=m;j>=;j--){

             if(i==n&&j==m) continue;

             if(fabs(-p[i][j].c)<1e-) continue;

             dp[i][j]=(p[i][j].r*dp[i][j+]+p[i][j].b*dp[i+][j]+)/(-p[i][j].c);

         }

         printf("%.3lf\n",dp[][]);

     }

     return ;

 }