Payment on a multiline Invoice

Developer101

Hello

This might be very basic question or it could be complicated.

I have an Invoice which is a multiline (means more that one item or GL account) one is lets say 450 line amount and other is 75 line amount. The total makes 525. So the total invoice invoice amount is 525.

Now the payment comes in for 50 which is only a part of 525. I then apply that payment to the Invoice. No issue the application goes fine and the remaining amount on invoice becomes 525-50 = 475

My question is how that payment of 50 is distributed between the two lines or items of an Invoice.
Basically the payment is allocated on both the lines of invoice and that is right but what is the formula behind it as to how the system knows what to distribute among the lines?

What is the formula behind it? I hope the question is clear.

satbir

Payment gets applied to full invoice.
There is no distribution among the invoice lines.