Following is the key in detail, i just implemented it in java:
import java.text.DecimalFormat;
public class test {
public static void main(String[] args) {
double sumP = 0.0;
for (int i = 11; i <= 35; i++) {
sumP += getCombination(i, 35)*Math.pow(0.1,i)*Math.pow(0.9, 35-i);
}
DecimalFormat df = new DecimalFormat("#.0000000");
String fP = df.format(sumP);
System.out.println(fP);
}
public static double getCombination(int r, int n){
return doFactorial(n)/(doFactorial(r)*doFactorial(n-r));
}
public static double doFactorial(int n){
if(n<0){
return -1;
}
else if(n==0){
return 1;
}
else if(n==1){
return 1;
}
else{
return n*doFactorial(n-1);
}
}
}
the result is 0.0004243