Maths question! Help!?

Question

My Granda asked me this question and hes a brilliant mathmaticion. But I could never work out the answer, heres the question.

3 men in a pub all have no where to live and they're all talking, but theres a landlord sitting next to them and the landlord says, ill rent you a flat for a week for £ 30. So he does and all the men are chuffed.

When the landlord got home he says to his self, i shouldnt of charged them £30 for the flat, it should of only been £25. The landlord says to his friend, run back to the pub and give them the money back. So hes does. butas the man is walking to the pub he says, how can i share £5 into 3 people? so the man says,ill give them all £1 each and ill keep £2 for a pint. So if 9+9+9=27 and the man buys his self a pint for £2 which = £29 where has the other £1 gone to

Answer 1

It's more like an accounting question because you must assume that the landlord and his friend are Sellers.

The guys paid £27 eventually.

The landlord lost £5, but his friend kept £2, so the Seller(landlord and his friend) actually lost £5-£2=£3

The buyers paid £30 but gained £3, so £30-£3=£27 paid to seller

Or the seller gained £30 but lost £3, so £30-£3=£27 received from buyers.

It's like you buy an item that costs £27, but pay £30, so the trader gives you £3 as change.

Answer 2

the landlord might have taken it himself or given it to his friend or  the man who nought the pint also took another pound.