Calculating net profit with VAT

In Question 293 of Kaplan revision kit, Victor style, they calculate the net profit after taking account of VAT like this:

Sales £9,500/month.
Purchases £400/month.

All figures are inclusive of tax. All sales and purchase are standard rated.

So the VAT payable for Victor (not enroll in flat rate scheme, he has registered VAT at the beginning of the tax year) is (9500×12)/6 – (400×12)/6 = £114,000/6 – £4,800/6 = £18,200

And then this is Kaplan’s solution for the profit as a result of the above sales and expenses:

Sales (£114,000 – 18,200): 95,800

Less:Exps (4,800-£800): (4000)

Net profit: £91,800

Can anyone please explain to me why Kaplan use the figure of £18,200 instead of £19,000? Because they still deducting £800 in the expenses below. So I’m not too sure why it’s possible to deduct the VAT for the expense twice. Is there any mechanism I should take caution of? Since Kaplan has almost no comment over this answer.