Do The Math
- Thread starter ZeeOSix
- Start date
Problem #2
Three guys get hotel room, the desk clerk charges them $30 (it's 1940, so hotels are cheap). He discovers he overcharged them as the room should have been $25. So, he gives the bellhop $5 to take to the men in their room. The bellhop decides there's no way to divided $5 by 3, so he gives the men $3 and keeps $2 for himself. That means each man paid $9 for the room and the bellhop kept $2. What happened to the other dollar?
Three guys get hotel room, the desk clerk charges them $30 (it's 1940, so hotels are cheap). He discovers he overcharged them as the room should have been $25. So, he gives the bellhop $5 to take to the men in their room. The bellhop decides there's no way to divided $5 by 3, so he gives the men $3 and keeps $2 for himself. That means each man paid $9 for the room and the bellhop kept $2. What happened to the other dollar?
17
There is no other dollar, each man should have paid $8.33, instead they paid $10. Clerk gave back $5, bellhop kept $2, meaning each man really paid $9.33 including tip.
Problem #1
10+10+10=30
10+5+5=20
5+2+2=9
5+2+10=17
Problem #2 The net transaction is $25. It is not $30 as implied by your question ...
$25=30-5=(3x10)-(3+2)=(3x10-3)-2=3(10-1)-2=3x9-2=$25
10+10+10=30
10+5+5=20
5+2+2=9
5+2+10=17
Problem #2 The net transaction is $25. It is not $30 as implied by your question ...
$25=30-5=(3x10)-(3+2)=(3x10-3)-2=3(10-1)-2=3x9-2=$25
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P#1
$15, pay attention to number of bags of fries in the pix.
You do multiplications before additions.
$15, pay attention to number of bags of fries in the pix.
You do multiplications before additions.
This is correct, it’s order of operations that is designed to trip you up in the last equation.
I have to celebrate @Skippy722 ’s taste in art though. It matches some of my own.
First problem:
Drink = 10
Burger = 5
Fries = 1
5 + (10 × 1) = 15
Drink = 10
Burger = 5
Fries = 1
5 + (10 × 1) = 15
15
The order of operations usually trips people up in these sorts of problems.
The order of operations usually trips people up in these sorts of problems.
Each guest paid $10, for a total of $30:
10 + 10 + 10 = 30
They were inadvertently overcharged. They should have been charged $25 in total. Each guest's share should have been $8.333 ... .
8.333... + 8.333 ... + 8.333 ... = 25
Therefore each guest was owed a refund of $1.667 ... .
The dishonest bellhop only refunded each guest $1, leaving each guest short $0.667.
The bellboy kept each guest's unrefunded portion - $0.667 x 3 = $2.
In the end, each guest paid $9, for a total of $27, for the $25 room.
The bellhop kep the difference of $2 ($27 paid vs. $25 nominal rental rate).
There was no magic missing dollar. The Warren Commission concluded that the bellhop had acted alone.
10 + 10 + 10 = 30
They were inadvertently overcharged. They should have been charged $25 in total. Each guest's share should have been $8.333 ... .
8.333... + 8.333 ... + 8.333 ... = 25
Therefore each guest was owed a refund of $1.667 ... .
The dishonest bellhop only refunded each guest $1, leaving each guest short $0.667.
The bellboy kept each guest's unrefunded portion - $0.667 x 3 = $2.
In the end, each guest paid $9, for a total of $27, for the $25 room.
The bellhop kep the difference of $2 ($27 paid vs. $25 nominal rental rate).
There was no magic missing dollar. The Warren Commission concluded that the bellhop had acted alone.
Not a trick question at all, but it trips up a few people:
Joe and John both empty their pockets and the amount of money they have together is exactly $20.
Joe had exactly $19 more money than John.
How much money did Joe have?
No, Joe did not have $19.
(Reader's Digest once said this question is commonly used on job interviews)
Joe and John both empty their pockets and the amount of money they have together is exactly $20.
Joe had exactly $19 more money than John.
How much money did Joe have?
No, Joe did not have $19.
(Reader's Digest once said this question is commonly used on job interviews)
A = money Joe had
B = money John had
A + B = 20 rewrite as B = 20 - A
A - B = 19 substitute from above A - (20 - A) = 19 -> A - 20 + A = 19 -> 2A = 19 + 20 so A = 39 / 2 = 19.50
Thus Joe had $19.50 and John had $0.50 which is exactly $19 less.
B = money John had
A + B = 20 rewrite as B = 20 - A
A - B = 19 substitute from above A - (20 - A) = 19 -> A - 20 + A = 19 -> 2A = 19 + 20 so A = 39 / 2 = 19.50
Thus Joe had $19.50 and John had $0.50 which is exactly $19 less.
