My favorite math “trick”:

[goldpan]

My favorite math “trick”:

(You probably have heard this before but has anyone figured out the answer?)

3 salesmen check into a hotel and agree to share the room.

The clerk tells them the room is $30 for the night, so they each chip in $10 (3×10=30, makes sense so far).

Well, it turns out there is a $5 discount for the room, so the manager tells the clerk to refund the money to the salesmen.
On the way to their room, the clerk pockets $2 for his troubles and gives the men the remaining $3.

The 3 men split the $3 refund.
So pay attention now:

Each paid $10 to start and got $1 back. 10-1= $9

3 x$9 =$27 The clerk had $2 of the refund.

$27 + $2= $29

Where did the 30th dollar end up???

[Afubar]

You're adding apples and oranges. Forget the 3 x 9. 30 minus 5 is 25. The 3 dollars returned to the guys plus the two kept by the clerk equals the five. The three guys should have paid 8.33333333 not the 9 but instead got ripped off.

[CLIFFTALL]

The room was only $25. The three men paid $27 and the clerk got $2.

[BFlinn181]

Afubar is correct, the sequence and math used to solve the problem is misleading. The room started out costing $30, divided by 3 men is $10 each. But, the room was actually only $25, divided by 3 men is $8.6666.
The clerk gave each man a dollar back from the $10 payment, so the men have now each paid $9, so they've paid $27 for a $25 room, or each paid $0.3333 MORE than they should. So, the men paid $27, the clerk kept $2, Three times $0.3333 equals $1; $27 + $2 + $1 totals $30.

[Fred1609]

I bet this only makes sense after a few pops.....

[NFlcamper]

Originally Posted by goldpan

My favorite math “trick”:

(You probably have heard this before but has anyone figured out the answer?)

3 salesmen check into a hotel and agree to share the room.

The clerk tells them the room is $30 for the night, so they each chip in $10 (3×10=30, makes sense so far).

Well, it turns out there is a $5 discount for the room, so the manager tells the clerk to refund the money to the salesmen.
On the way to their room, the clerk pockets $2 for his troubles and gives the men the remaining $3.

The 3 men split the $3 refund.
So pay attention now:

Each paid $10 to start and got $1 back. 10-1= $9

3 x$9 =$27 The clerk had $2 of the refund.

$27 + $2= $29

Where did the 30th dollar end up???

Misdirection: 10x3 = 30 (OK)
3x9=27 (OK, what they paid after $3 refund NOT $5 refund)
27+3=30 (They think the room was 27 after rebate - the other $1 is in each of their pockets)
30-5 =25 (actual cost - not what they were told)
25+2=27 (actual cost+$2 stolen) - then add back $3 in their pockets = $30

We were misdirected to think there was only another $1 when $2 was actually stolen! = GOVERNMENT MATH!

[Ray,IN]

An old saying: Liars figure, figures lie.

[Cliffy]

My head hurts!