How to reads customer number and power consumed and prints amount to be paid using C

An electric power distribution company charges its domestic consumers as follows

Consumption   Rate of Units Charge
  ------------------------------------
  0-200       Rs.0.50 per unit
  201-400     Rs.100 plus Rs.0.65 per 
              unit excess 200
  401-600     Rs.230 plus Rs.0.80 per 
              unit excess of 400.
  ------------------------------------

Write a C program that reads the customer number and power consumed and prints the amount to be paid by the customer.

Program :

#include <stdio.h>
#include <conio.h>

void main() {

   int cust_no, powerUsage;
   float amount;
   clrscr();

   printf("Enter the customer number: ");
   scanf("%d", &cust_no);
   printf("Enter the power consumed: ");
   scanf("%d", &powerUsage);

   if (powerUsage >= 0 && powerUsage <= 200) amount = powerUsage * 0.50; else if (powerUsage > 200 && powerUsage < 400) amount = 100 + ((powerUsage - 200) * 0.65); else if (powerUsage > 400 && powerUsage <= 600)
      amount = 230 + ((powerUsage - 400) * 0.80);
   
   printf("Amount to be paid by customer no. %d is Rs.:%5.2f.", cust_no, amount);

   getch();
}

Output :

Enter the customer number: 1
Enter the power consumed: 100
Amount to be paid by customer no. 1 is Rs.:50.00.