My Math Forum  

Go Back   My Math Forum > College Math Forum > Applied Math

Applied Math Applied Math Forum

LinkBack Thread Tools Display Modes
September 7th, 2010, 12:06 PM   #1
Joined: Sep 2010

Posts: 1
Thanks: 0

Logic formula for calculating a customer's deposit.

Hi Everyone and thanks for the help!

I'm new to this forum and I don't know how i'm going to explain my problem, but i'll do my best.

I'm trying to calculate how much of a deposit a customer will make depending on the sale price of an item.

Here are the details:

Deposit amount = (Final Price- Base Price)*50%

I would like the customer to make this calculation themselves by having a webpage with a textbox and a button that uses the formula. The customer would simply INPUT the Final Price amount and get an OUTPUT of the Deposit Amount.

The problem is that I don't want the customer to be able to figure out the Base Price. If a customer enters in various numbers into the text box they can figure out the Base Price when the output becomes zero. E.g. ($5,000-$5,000)*50%= 0.

In order to mask the Base Price I was trying to come up with a formula that will only show a zero output when the customer inputs a Final Price of zero. So in other words, the formula only needs to make accurate calculations beyond a minimum output of say $400.

This is what I have so far (and this is where i'm truly stuck):
By the way, I was using Excel to calculate this. That's why it's in this format.

IF((Final Price- Base Price)*50%)>400, (Final Price- Base Price)*50%, if not then the output will slowly taper down to zero and only be zero when the input is zero.

I wrote the last part in plain english because that's wehre i'm having the most trouble expressing it as a mathematical formula.

Once again the goal is to mask the inner workings of the formula so that the customer cannot easily figure out the Base Price when they're entering various Inputs. The only way I can figure out how to mask this is to only make the formula accurate beyond a certain output. Maybe there's another way of masking it though.

Let me know if you need more information... Logic was never my strong suit (or even math) so this would be a big help to me.

jamesg is offline  
September 7th, 2010, 05:37 PM   #2
Global Moderator
The Chaz's Avatar
Joined: Nov 2009
From: Northwest Arkansas

Posts: 2,766
Thanks: 4

Re: Logic formula for calculating a customer's deposit.

Hopefully this won't be an oversimplification.
D = (F - B) * 50%
D = (F - B) *(.5)
D = .5F - .5B
Let's use your example of $5000 for the base amount.
So the output is just .5F - .5*5000
= .5F - 2500

The reason that I wrote it that way is so that we can agree that it is SIMPLE (nothing simpler than a straight line!). Anyone testing two points could immediately deduce the base amount (if they assume that it's linear, which any amount of trials will support).

So you might not find a simple answer. Sure, you could write a conditional program, but that's not going to make it any harder to "guess" your base amount.

The Chaz is offline  
September 7th, 2010, 08:00 PM   #3
Senior Member
MarkFL's Avatar
Joined: Jul 2010
From: St. Augustine, FL., U.S.A.'s oldest city

Posts: 12,211
Thanks: 520

Math Focus: Calculus/ODEs
Re: Logic formula for calculating a customer's deposit.

I agree with what The Chaz is saying...if the user knows the deposit amount is half the difference of the final price and the base price, there's not much you can do to keep the mathematically inclined from easily deducing the base price.

However...given the rampant innumeracy in our society (i.e American, I'm not going to speak for other societies), where people are proud to declare they can't even balance their checking accounts, how many folks out there are going to even be aware that it is possible to solve the relationship for the base price?
MarkFL is offline  
September 7th, 2010, 08:13 PM   #4
Global Moderator
The Chaz's Avatar
Joined: Nov 2009
From: Northwest Arkansas

Posts: 2,766
Thanks: 4

Re: Logic formula for calculating a customer's deposit.

The 9132 registered users of "", minus the bots and spammers?
The Chaz is offline  

  My Math Forum > College Math Forum > Applied Math

calculating, customer, deposit, formula, logic

Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
How to find the compound amount for the following deposit ? fawazalusail Algebra 4 November 6th, 2012 08:00 PM
formula for calculating an changing percentage Leander Applied Math 0 February 3rd, 2012 02:04 PM
Customer life flapalot Algebra 1 January 30th, 2012 06:06 AM
Urgent Help:Formula For Calculating Ratings of Products? tvadmin516 Applied Math 1 November 18th, 2011 07:11 AM
Customer sales Dld3 Economics 3 November 2nd, 2011 12:17 PM

Copyright © 2019 My Math Forum. All rights reserved.