Cash Management - Forecast sales treatment of bad debts

I am self studying level 3 using BPP text books and would appreciate any guidance on the following:

In the BPP text it is advised that bad debts are debited from the final month sales percentage e.g:

Month sales are £100,000 and 25% is in 30 days, 50% 60 days, 25% 90 days, 5% of all invoices are expected to be bad debts.

In the text we treat the bad debt only in month 3 (90 days) by deducting (bad debts) 5% from 25%, then calculate 20% of £100k = £20k e.g:

Month 1
£100,000 x 25% = £25,000
Month 2
£100,000 x 50% = £50,000
Month 3
£100,000 x (25%-5%)= £20,000
Total = £95,000

This makes sense to me and I thought I understood the concept.

I then tried AAT Practice CBT 2, Q2.1 which has a 5% bad debt to be calculated.
I have worked out that the AAT answer uses the following equation for all three periods:

Amount x month percentage x 95%.

Using my previous example it would be:

Month 1
£100,000 x 25% x 95% = £23,750
Month 2
£100,000 x 50% x 95% = £47,500
Month 3
£100,000 x 25% x 95% = £23,750
Total = £95,000

THe total is the same but it is spread over all three periods using the AAT answer.

The only difference is that Q2.1 has the following wording following the amounts and monthly percentages:
The revised receipt pattern is to be applied after assuming that 5% of all sales will be bad debts.

My exam is this Thursday and without being able to seek tutor support for this module I am stuck. Help would be very much appreciated.

Thanks.
:huh: