Brain teaser

[Raffaz]

Ok, this isn't really a joke but it came up on a team build once.
It will still confuse anyone you run it past.

Three students decide to club together to buy a TV.

They see one in a shop for £30.

They buy the TV, and each of them hands over a £10 note.

The shopkeeper tells them that it is ex-demo and so he'll knock £5 off the price.

He hands back 5 pound coins.

To keep things simple, each student takes £1 and they put the spare £2 into a charity tin on the counter.

The problem is, now each of them has handed over £9 (£10 and received £1 back).

3 x £9 is £27.

There is £2 in the charity tin.

£27 + £2 = £29.

Where is the remaining £1 from the original £30 they paid?

Il post the answer later, if no one gets it

 

[Tommy Boy]

It's all in the order in which you do the math.

30 for the tv

He says he'll take 5 off for it being a demo

25 for the tv

each person takes 1 dollar back

25 + 3 = 28

plus the 2 in the charity bin

28 + 2 = 30

 

[freestyler105]

Alright, I've been thinking about this for like 10 minutes so far.

The owner has 25.

Assuming each student only brought 10 into the store, they all have 1.

The charity bin has 2

25+3+2=30.


EDIT - Ah, Tommy beat me.

 

[Raffaz]

Hmmm sort of, but there is an error in the first post if you look

 

[freestyler105]

Ok, so when you say

£27 + £2 = £29

It should really be

£27 - £2 = £25.

To show how much they paid. And then 30-25= the 5 they got back.

 

[muz]

as above , it is in the order you say it cos ,
the shop has £25
each student has £1
and the charity bin has £2
so 25+3+2=30

 

[Raffaz]

Well ya just about there. The £27 is the cost of the TV AND the £2 that went in the charity tin. That last bit of the puzzle is misleading because the charity tin donation has already been included in the total cost so you shouldn't be adding it on again.

 

[freestyler105]

Oh....I hate brain teasers.

 

[Bahawolf1]

This was definitely a brain teaser for some, but for me, I honestly noticed it almost immediately.

 

[David Lindon]

Well ya just about there. The £27 is the cost of the TV AND the £2 that went in the charity tin. That last bit of the puzzle is misleading because the charity tin donation has already been included in the total cost so you shouldn't be adding it on again.

Ah I get it, had me puzzled there for a few minutes there.

Not to hijack this thread, but can anyone remember the solution to the 3 gallon and 5 gallon jugs trying to make 4 gallons?