Help me in solving RCPITCP44 problem

help
,
1

My issue

Not able to solve problems

My code

#include <stdio.h>

int main() {
    float x, a;
  int length = 11;
  // Update your code below this line
   printf("x %=3");
   a = lenght/x;
   printf("%f",a);
  
  
}

Learning course: Learn C Programming
Problem Link: https://www.codechef.com/learn/course/rcpit-programming-c/RCPITLPC08/problems/RCPITCP44