View Full Version : Simple math riddle - who can solve it?
Black Panther
03-24-2011, 06:42 PM
3 guys decide to buy a gift for their boss so each of them forks out $10.
They give these $30 to a young messenger and send him to buy the gift.
However the messenger spends only $25.
Upon returning, the messenger tells them he's got change, so he keeps $2 for himself for doing the job and gives back $1 to each of the 3 men.
The 3 guys were happier now because they had spent $9 each for the boss' gift.
The messenger was happy too because he earned $2.
_______________________________
Now $9 x 3 = $27.
The messenger kept $2 for himself.
That totals $29.
What happened to the other dollar??
Nailezs
03-24-2011, 06:48 PM
you ever have the feeling when you're thinking about something or trying to understand something that you hit this giant brick wall in your head? yeah, i keep hitting that. repeatedly.
get me over the brick wall, BP
EDIT: i think i get it. dude gave the guys incorrect change. 25/3 is 8.33
they should have gotten .66c back, not $1. so .66 x 3 = $2 (ok, its 1.98c but its really .66666666 you get the picture? thats the deicmal equivalent of 2/3. 1/3 x 3 = 2.) EDIT3: so the extra $1 actually went to the guys because they were given 33c more change than they should have
right?
YAY!
EDIT2: damnit its still not working right in my head but i know im on the right track
EDIT4: in effect they did not spend $9 they spent $9.33 which is where the extra dollar went
YAY I FIGURED IT OUT!!!!!
twilyth
03-24-2011, 06:56 PM
They gave him $27 and the gift cost $25 so the difference is the $2 he kept.
Its not really a riddle, its just a mindfuck, a matter of how you look at it.
Nailezs
03-24-2011, 07:00 PM
They gave him $27 and the gift cost $25 so the difference is the $2 he kept.
They give these $30 to a young messenger and send him to buy the gift.
no, they gave gim $30...
EDIT: check my 4 edits in order in my orig post. i did it!
i r gen-ass!
Black Panther
03-24-2011, 07:13 PM
They gave him $27 and the gift cost $25 so the difference is the $2 he kept.
They gave him $30 in the first place, not $27.
Out of the $5 change he gave each of them $1 (so they went only $9 out of pocket instead of $10) and kept $2 for himself.
And here we go again... $9x3=$27... + the $2 he kept for himself... (▲)
________________________________
25/3 is 8.33
they should have gotten .66c back, not $1. so .66 x 3 = $2 (ok, its 1.98c but its really .66666666 you get the picture? thats the deicmal equivalent of 2/3. 1/3 x 3 = 2.) EDIT3: so the extra $1 actually went to the guys because they were given 33c more change than they should have
right?
YAY!
EDIT2: damnit its still not working right in my head but i know im on the right track
EDIT4: in effect they did not spend $9 they spent $9.33 which is where the extra dollar went
YAY I FIGURED IT OUT!!!!!
No...
the messenger had a square $5 in his pocket. He kept $2 for himself and divided the remaining $3 between the 3 guys so they got $1 each.....
i did it!
i r gen-ass!
No you didn't ;)
I know how to solve it but I don't want to spoil BPs fun.
WhiteLotus
03-24-2011, 07:19 PM
£30 given, £25 spent
£5 saved, £1 given back to each guy, £2 kept.
so
£25 spent+£3+£2=£30.
£30=£30
There is no extra £, it's a riddle out of nothing.
£30 given, £25 spent
£5 saved, £1 given back to each guy, £2 kept.
so
£25 spent+£3+£2=£30.
£30=£30
There is no extra £, it's a riddle out of nothing.
Okay well done Mr. Spoil-the-fun :p
Anyways yes thats how it works. Its a simple matter of how you look at it.
Especially the last equation in the "riddle" leads you on a wrong path.
Black Panther
03-24-2011, 07:23 PM
£30 given, £25 spent
£5 saved, £1 given back to each guy, £2 kept.
so
£25 spent+£3+£2=£30.
£30=£30
There is no extra £, it's a riddle out of nothing.
get me over the brick wall, BP
I know how to solve it but I don't want to spoil BPs fun.
I understand WhiteLotus' way makes sense... but
Put yourself in the shoes of one of those guys, imagine you're one of them..
You originally forked out $10, and the messenger gave you back $1. That means your cost was $9. Same goes for the other 2 of your mates. Each contributed $10 and got $1 back so they actually lost only $9 out of their pockets.
$9 contributed by 3 guys means that they spent a total of $27.
The messenger kept $2.
The total of that is $29........... :eek:
[Edit: btw I don't know the 'solution' either... :o]
But put yourself in the shoes of one of those guys. You originally forked out $10, and the messenger gave you back $1. That means your cost was $9. Same goes for the other 2 of your mates. Each contributed $10 and got $1 back so they actually lost only $9 out of their pockets.
$9 contributed by 3 guys means that they spent a total of $27.
The messenger kept $2.
The total of that is $29........... :eek:
No they still spent 30$ in total.
They just got each 1$ back = 3$ total
And 2$ for the guy
25+3+2 = 30.
The key point here is that you can not assume that the three guys spent 9$. They still spent 10, just got 1$ back.
I'll do a chart.
WhiteLotus
03-24-2011, 07:27 PM
It doesn't matter, every £ is accounted for. It's not a riddle, just mathematics doing a gay on you.
http://img.techpowerup.org/110324/math.jpg
See?
Black Panther
03-24-2011, 07:35 PM
you can not assume that the three guys spent 9$. They still spent 10, just got 1$ back.
I'll do a chart.
If you spend $10 and get $1 back how much would you have spent?
http://www.subzerosiam.com/forum/images/smilies/confused-8.gif
WhiteLotus
03-24-2011, 07:38 PM
£9.
You can either look at it from a mathematics point of view which is where this "riddle" comes in, or you look at it from the real point view, where every £ is accounted for.
If you spend $10 and get $1 back how much would you have spent?
http://www.subzerosiam.com/forum/images/smilies/confused-8.gif
Ten dollars. Who became a grand total of 30.
NOW you have to calculate with this 30, the individual 10 are no more part of this situation.
You pay 25, get five back from the GRAND TOTAL. Thats a NEW total of 5.
You split those 5 in 1 1 1 and 2.
So, 2+1+1+1=5+25=30/3=10, that is the correct equation.
Don't be fooled by the dollar back, it just fucks with you. Its not part of the calculation, thus there appears this "missing dollar".
Black Panther
03-24-2011, 07:47 PM
Mathematically £25 spent+£3+£2=£30 obviously...
But in real life you and your pals would really have spent $9, and the messenger would really have kept $2. However at the end of the day in real life all of the $30 is distributed..
http://img.techpowerup.org/110324/math164.jpg
I'm ready to bet that this is the way governments collect taxes...... :D
Mathematically £25 spent+£3+£2=£30 obviously...
But in real life you and your pals would really have spent $9, and the messenger would really have kept $2. However at the end of the day in real life all of the $30 is distributed..
http://img.techpowerup.org/110324/math164.jpg
I'm ready to bet that this is the way governments collect taxes...... :D
How dare you use my brilliant graph :D
Anyway you have to differ between math and real life. Or, between reality and what you think. YOU think you got one buck back. In reality your money joined communism, and what was left was spread evenly again.
It really fucks with your mind, really. REALLY
Black Panther
03-24-2011, 07:59 PM
Ten dollars. Who became a grand total of 30.
NOW you have to calculate with this 30, the individual 10 are no more part of this situation.
You pay 25, get five back from the GRAND TOTAL. Thats a NEW total of 5.
You split those 5 in 1 1 1 and 2.
So, 2+1+1+1=5+25=30/3=10, that is the correct equation.
Don't be fooled by the dollar back, it just fucks with you. Its not part of the calculation, thus there appears this "missing dollar".
There's a large invisible penis mindfuck here.
It gets more complicated if you imagine that you are one of those 3 guys.
If you contributed $10 and got $1 back in change there's no way you can insist that you paid $10. Try saying so to the other 2.....
You paid $9, and so did your other 2 mates who also paid $10 and each got $1 in return.
The messenger only kept $2.
Sure the totals kept by you and your mates total $3 and the messenger kept $2 so that makes $5 and everything is fine........
But you and your 2 mates paid $9 since you all got $1 change.
And 9x3=27.
So all three of you only paid $27. The messenger kept $2 tips.
Now what?
There's a large invisible penis mindfuck here.
It gets more complicated if you imagine that you are one of those 3 guys.
If you contributed $10 and got $1 back in change there's no way you can insist that you paid $10. Try saying so to the other 2.....
You paid $9, and so did your other 2 mates who also paid $10 and each got $1 in return.
The messenger only kept $2.
Sure the totals kept by you and your mates total $3 and the messenger kept $2 so that makes $5 and everything is fine........
But you and your 2 mates paid $9 since you all got $1 change.
And 9x3=27.
So all three of you only paid $27. The messenger kept $2 tips.
Now what?
Nothing, everything is fine, move along Ma'am ;)
You still paid 10 bucks, but in the end it looks like you only spent 9. But you did spent 10 and got 1 back. It seems that the three guys spent 27 in the end, but they really did spend 30.
Nailezs
03-24-2011, 08:15 PM
so far as i can tell only BP and I understand the actual riddle.
BP do you understand my mathematical explanation? if not i will try and simplify it.
so far as i can tell only BP and I understand the actual riddle.
BP do you understand my mathematical explanation? if not i will try and simplify it.
Sheesh I get it, theres a dollar missing yadda yadda yadda. The "riddle" however exists only in your brain.
Tried a mathematics forum yet? There are tons of threads about this same riddle.
FordGT90Concept
03-24-2011, 08:19 PM
What happened to the other dollar??
The messenger gave it to himself because he was one of the three.
$25 spent, $2 to messenger, $1 to A, $1 to B, $1 to C = $30
A/messenger spent $9 = $2 for delievery, $7 for the gift.
B spent $9 = $9 for the gift
C spent $9 = $9 for the gift
Black Panther
03-24-2011, 08:29 PM
The messenger gave it to himself because he was one of the three.
No the messenger didn't contribute to buying the gift. He just took the $30, bought a $25 gift, kept $2 for the trouble and gave $1 each to the other 3 guys who had forked out $10 in the first place.
Thanks to the messenger giving them $1 back each, now instead of $10 each they contributed $9 each towards the boss' gift. :)
Nothing, everything is fine, move along Ma'am ;)
You still paid 10 bucks, but in the end it looks like you only spent 9. But you did spent 10 and got 1 back. It seems that the three guys spent 27 in the end, but they really did spend 30.
So, you're saying that if I spend 10 bucks and get one buck back in change, I can still insist that I spent 10 bucks and not 9? How could 3 guys give out $30 between them, receive $3 to be divided back between them, and insist that they still spent $30?
No the messenger didn't contribute to buying the gift. He just took the $30, bought a $25 gift, kept $2 for the trouble and gave $1 each to the other 3 guys who had forked out $10 in the first place.
Thanks to the messenger giving them $1 back each, now instead of $10 each they contributed $9 each towards the boss' gift. :)
So, you're saying that if I spend 10 bucks and get one buck back in change, I can still insist that I spent 10 bucks and not 9? How could 3 guys give out $30 between them, receive $3 to be divided back between them, and insist that they still spent $30?
Perception ;)
Black Panther
03-24-2011, 08:44 PM
Perception ;)
Sure. Try to explain it to your bank if they give you a loan for $10 and you insist that you used $9... (ww)
Sure. Try to explain it to your bank if they give you a loan for $10 and you insist that you used $9... (ww)
I think we could argue back and forth for eons.
razaron
03-24-2011, 09:38 PM
9*3=27
27-2=25
The gift cost 25.
jmcslob
03-24-2011, 11:17 PM
10$+10$+10$=30$
Gift=25$
3x1$ given back and 2$ kept for delivery
so it it would be
3x10=x-25=y-2 /3
30-25=5
5-2=3
3/3=1
Nailezs
03-24-2011, 11:31 PM
that equation makes no sense, but come to think of it, maybe its not supposed to lol
Fourstaff
03-24-2011, 11:35 PM
An alternative found in Trollscience:
Get a friend, and both of you put $20 in to a box. Sell the box to your friend for $30, and since that there is $40 in the box, both of you earn $10!
jmcslob
03-24-2011, 11:37 PM
Don't think of it as an equation
Think of it as a statement of Accountability
DrPepper
03-25-2011, 12:20 AM
An alternative found in Trollscience:
Get a friend, and both of you put $20 in to a box. Sell the box to your friend for $30, and since that there is $40 in the box, both of you earn $10!
But you don't both earn £10.
Bundy
03-26-2011, 06:27 AM
lol.
Post No.3, Twilyth solved the riddle but he was ignored.
Using BP's way of expressing the problem is where the riddle is formed.
It is not 3x9 =27, then add 2 = 29
It is how twilyth put it 3 x 9 = 27 then subtract 2 = 25 = the value of the gift.
Nailezs
03-26-2011, 12:02 PM
They gave him $27 and the gift cost $25 so the difference is the $2 he kept.
lol.
Post No.3, Twilyth solved the riddle but he was ignored.
Using BP's way of expressing the problem is where the riddle is formed.
It is not 3x9 =27, then add 2 = 29
It is how twilyth put it 3 x 9 = 27 then subtract 2 = 25 = the value of the gift.
while i am fully aware that the gift costs $25, and in fact compensated for that in my little explanation in post #2, i have no clue wth u and twilyth are talking about. if you take the $2 out of the $27 you're taking the $2 from the change + cost of the gift, which was not done.
A Cheese Danish
03-26-2011, 12:20 PM
Look.
First part: $30
Each person gave $10 to the messenger. He purchased a gift for $25.
$30-$25 = $5.
Messenger kept $2, ($3 left), and gave each person back $1 ($0 left)
Second part: $29
Each person thought they only had to pay $9.
$9 * 3 = $27
Gift = $25. $27-$25 = $2 left over. Messenger still keeps the $2; the others do not know he kept it.
Nailezs
03-26-2011, 12:24 PM
ok, so whered the rest of the $30
twilyth
03-26-2011, 12:26 PM
while i am fully aware that the gift costs $25, and in fact compensated for that in my little explanation in post #2, i have no clue wth u and twilyth are talking about. if you take the $2 out of the $27 you're taking the $2 from the change + cost of the gift, which was not done.
since they each get a dollar back you can regard their original expenditure as being $9 rather than $10.
If I have a dollar off coupon for a $10 item and I use the coupon to buy the item, did it cost me $9 or $10?
lol.
Post No.3, Twilyth solved the riddle but he was ignored.
Using BP's way of expressing the problem is where the riddle is formed.
It is not 3x9 =27, then add 2 = 29
It is how twilyth put it 3 x 9 = 27 then subtract 2 = 25 = the value of the gift.
Um twilyth said they paid him 27 but they paid 30 - you can't just ignore the three bucks there.
A Cheese Danish
03-26-2011, 12:29 PM
ok, so whered the rest of the $30
$30-$25 = $5.
Messenger kept $2, ($3 left), and gave each person back $1 ($0 left)
Change from gift: $5
Messenger: $2
Each person: $1
$5 - $2 - $1 - $1 -$1 = 0 <== Shows all the $30 was used. $25 for gift, $2 for messenger, $1 for each person (so $3)
http://img.techpowerup.org/110324/math164.jpg
Okay BP. What you did was a calculation error. The original $30 is from all 3 guys giving $10 each.
So, when they all thought paying $9 was better, the total from that would only be $27, not $29.
You were adding money that wasn't there. The messenger doesn't take his cut until AFTER the gift is purchased.
Like I said in my above post; the equation has 2 parts that everyone is forming into 1 equation that just doesn't work.
twilyth
03-26-2011, 12:42 PM
Um twilyth said they paid him 27 but they paid 30 - you can't just ignore the three bucks there.
but they got $3 back. OK, so it's more like a mail in rebate than a coupon.
brandonwh64
03-26-2011, 01:00 PM
taxes... what a bitch
de.das.dude
03-26-2011, 01:33 PM
what you guys are doing is. not thinking of the messenger and the guy as separate.
lets say the messenger is spending 30$. he spends 25$ and so has 5$ left. he spends 2 on a cheezburger and has 3 left.
but if you want to consider the 3 guys,
lets consider the left side as the 3 guys pockets and right as how they spend it.
10+10+10=25(gft)+2(comission)+3(yay!)
since 3 is returned, we bring it back to the guys pocket
10+10+10-3=25+2
so
10+10+10-3=25+2
here is where the troll confused us.
instead of 10+10+10-3-2
=> 9*3-2 = 25
what it did was add the 2 dollars to what the guys had. which is wrong as sign is wrong
which is just sad.
Black Panther
04-03-2011, 07:57 PM
All right, another one:
http://img.techpowerup.org/110403/economy.jpg
*goes back to the kitchen, my intelligence is better suited to the making of sammiches* :p
Bundy
04-04-2011, 04:49 AM
All right, another one:
http://img.techpowerup.org/110403/economy.jpg
*goes back to the kitchen, my intelligence is better suited to the making of sammiches* :p
More feline number trolling. Challenge accepted.
The problem with this problem is governance. Poor governance. The two parties who set up the trust fund (aka the box) should also have appointed an independant accounting person to oversea divestment of funds. Lack of proper accounting and auditing has allowed one partner to misappropriate funds.
Person 1 contributes $20, fund now balances $20.
Person 2 contributes $20, fund now balances $40.
Entire fund sold to person 2 for $30, balance $30.
Balance of fund returned to person 1, balance now $0
Person 1 contributes a total of $20 and gets $30 back. Winner(toast)
Person 2 contributes a total of 20+30=$50 and gets $40 back. Loser (nutkick)
de.das.dude
04-05-2011, 03:34 AM
this didnt even troll me.
Namslas90
04-05-2011, 07:28 AM
*goes back to the kitchen, my intelligence is better suited to the making of sammiches* :p
Your hired, been looking for a new live in chef.
MoonPig
04-05-2011, 10:34 AM
Lol, BP... How did this thread get some many of the same, right answer, yet no conclusion... :p
scaminatrix
04-23-2011, 06:40 PM
So all three of you only paid $27. The messenger kept $2 tips.
Now what?
The $2 the messenger keeps is already covered in the $27:
Item cost $25, messenger keeps $2 = $27 + $3 change = $30
The answer is: you're counting the messenger's money twice.
yogurt_21
04-25-2011, 06:25 PM
25/3 does not equal 8$ it's 8.33 repeating. add a dollar to it and you get 9.33 repeating. by 3 that becomes 28$
this is merely a story of the order of operations.
30-5 (the original transaction) =25
5-2 (the savings minus amount the guy kept) =3
25+3 (the amount spent plus the amount returned) =28 gasp....does that plus 2 = 30? I think it does!
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