Formula for Discount calculation

Question

I have face the problem,i need to calculate the final amount if there is any booking fee and we charge service tax as 15% ST. If there is no Booking Fee then no ST,and if discount is there then we minus discount(percentage field) from the ticket price. It was working fine but now we offer discount amount(currency),but is not working.

My formula is

( (Quantity* UnitPrice ) - Discount_Amount__c ) + 
Booking_Fees_Amount__c + 
((((Quantity* UnitPrice ) - Discount_Amount__c )+ Booking_Fees_Amount__c)*PG__c) + 
ST_15_on_Booking_Fees__c

Discount_Amount_c is Percentage and Discount_c is Currency.

In my case sometime we give Discount percentage as well as whole amount percentage is working fine but whole amount is not working fine

Answer 1

As per my understanding, you need to breakup the requirement in small parts like this:

Quantity 10 and price is 500 and my booking fee is 100 (per ticket) 5000+1000

(Quantity * UnitPrice) + (Booking_Fees_Amount__c *  Quantity)

I charge ST as 15%. Final calculation is like 6150 (5000+1000+150 )

((Quantity * UnitPrice) + (Booking_Fees_Amount__c *  Quantity))
* (1 + ST_15_on_Booking_Fees__c)

If my discount will 10% then final amount will 5650, now i need add discount as amount same

(((Quantity * UnitPrice) + (Booking_Fees_Amount__c *  Quantity))
 * (1 + ST_15_on_Booking_Fees__c)) 
* (1 - Discount_Amount__c)

Answer 2

Discount_Amount_c is Percentage and Discount_c is Currency.

• Field names are sugesting it's an opposite - am I right stating Discount_Amount_c is Currency and Discount__c is Percentage?
• Can these 2 from the above apply at the same time?

(( Quantity * ((10 *

UnitPrice * (1 - Discount__c)) <- 10% discount 10*(500 * (1-0.1)) = 4,500

- Discount_Amount__c <- $ discount any? = 4,500 - x

+ Quantity * Booking_Fees_Amount__c * (1 + ST_15_on_Booking_Fees__c) <- booking fee + 15% service tax 4,500 + 10 * 100 * 1.15 = 5,650

• is PG__c a "whole amount percentage"?

) * (1 - PG__c) 5650 * [additional 10%] 0.9 = 5,085