required calculations should be done after data entered by the user.
so, below, run fines:
#include <stdio.h>
int main()
{
float salary , hours , num ;
printf("Enter Your Salary in Month\n");
scanf("%f" ,&salary);
printf("Enter a hours you work in Month\n");
scanf("%f" ,&hours);
num = salary/hours;
int intpart = num;
int decpart = 100*(num-intpart);
printf("Your average hourly pay rate is %d EGP and %d piastres \n" ,intpart,decpart);
return 0;
}