Riddles / brain benders

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Post 3+ Months Ago

This is one of my favorite math riddles. It requires no calculator, computer, or even pencil and paper. Just think about it!

A businessman commutes home from the office, and his train gets into the station in his home town exactly at the same time every day. Every day his chauffeur is there to pick him up and take him home, so that every day he arrives home at exactly the same time. Everything works like clockwork, so well in fact that the chauffeur is in the practice of timing his arrival at the station to exactly coincide with the arrival of the train.

One day, however, the businessman decides to leave work early, and he catches a train that gets to his station an hour early. He forgot to call ahead, so his chauffeur is not there to pick him up. The businessman decides that rather than wait for the chauffeur, he will start to walk home. Some time later the chauffeur comes driving along on his way to the station, sees his boss walking along the road, so he stops to pick him up, and they drive on home.

As the businessman walks in the front door of the house his wife exclaims, "Oh, honey, how nice -- you're home 20 minutes early!"

Question: how long was the man walking along the road before the chauffeur picked him up?

As usual with these types of problem, assume everything works nicely: constant velocity of the chauffeur's car, instant pick up and turn around, the train is always exactly on time, etc, etc.
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Post 3+ Months Ago

there are two sons and a dad, a row boat and a river to cross.


each son weighs 75lbs
the dad weighs 150lbs

the row boat capacity is 150lbs

they all need to get accross the river, how can they do this with out ropes or any fancy tricks?
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Post 3+ Months Ago

Three men were on a business trip and had to stay in a hotel
over night. The price of the room was $30.00, so the men
decided to split one room, three ways. Each one paid $10.00.
Well after they paid, the manager realized that he overcharged
them on their room. The room only cost $25.00, so he gave the
bellboy five one dollar bills to give to the three men. On his
way up to the room the bell boy was trying to think of a way to
split $5.00 three ways. After thinking about it awhile, he decided
to keep $2.00 for himself and give each man $1.00 back. Now, if
each man (who paid $10) gets $1 back that means they each paid
$9.00 ($10 - $1 = $9 ). $9.00 multiplied by 3 (because there are
three men) equals $27.00 plus the $2.00 the bell boy kept equals
$29.00! What happened to the missing dollar?????
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Post 3+ Months Ago

Gadget Guru wrote:
This is one of my favorite math riddles. It requires no calculator, computer, or even pencil and paper. Just think about it!

A businessman commutes home from the office, and his train gets into the station in his home town exactly at the same time every day. Every day his chauffeur is there to pick him up and take him home, so that every day he arrives home at exactly the same time. Everything works like clockwork, so well in fact that the chauffeur is in the practice of timing his arrival at the station to exactly coincide with the arrival of the train.

One day, however, the businessman decides to leave work early, and he catches a train that gets to his station an hour early. He forgot to call ahead, so his chauffeur is not there to pick him up. The businessman decides that rather than wait for the chauffeur, he will start to walk home. Some time later the chauffeur comes driving along on his way to the station, sees his boss walking along the road, so he stops to pick him up, and they drive on home.

As the businessman walks in the front door of the house his wife exclaims, "Oh, honey, how nice -- you're home 20 minutes early!"

Question: how long was the man walking along the road before the chauffeur picked him up?

As usual with these types of problem, assume everything works nicely: constant velocity of the chauffeur's car, instant pick up and turn around, the train is always exactly on time, etc, etc.


The businessman got home 20 min early which means that the Chauffer saved 10 min each way. What that means is that the businessman had to be walking for 10 min in order to save 10 min for one of the ways for the Chauffer.
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Post 3+ Months Ago

Gadget Guru wrote:
there are two sons and a dad, a row boat and a river to cross.


each son weighs 75lbs
the dad weighs 150lbs

the row boat capacity is 150lbs

they all need to get accross the river, how can they do this with out ropes or any fancy tricks?


First the two sons who weight 75 lbs go across the river. Then one stays and the other comes back and gets out. Then the dad who weights 150 gets in and goes across the river and gets out. Now the son that weighs 75 lbs gets back in and goes across the river to get the other son, for which they can both now be in the row boat to cross the river. They are now all across the river :)
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Post 3+ Months Ago

very nice sir, now that last one is a real bender.. good luck.. hehe
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Post 3+ Months Ago

Gadget Guru wrote:
Three men were on a business trip and had to stay in a hotel
over night. The price of the room was $30.00, so the men
decided to split one room, three ways. Each one paid $10.00.
Well after they paid, the manager realized that he overcharged
them on their room. The room only cost $25.00, so he gave the
bellboy five one dollar bills to give to the three men. On his
way up to the room the bell boy was trying to think of a way to
split $5.00 three ways. After thinking about it awhile, he decided
to keep $2.00 for himself and give each man $1.00 back. Now, if
each man (who paid $10) gets $1 back that means they each paid
$9.00 ($10 - $1 = $9 ). $9.00 multiplied by 3 (because there are
three men) equals $27.00 plus the $2.00 the bell boy kept equals
$29.00! What happened to the missing dollar?????


Well the 3 men in reality did not save 5 dollars. They only saved 3 and that is why it cost them 27. Now it would have cost them 25 bucks. So as you can see 27-25 = 2, which is what the bell boy kept. You added 27+2 when it should have been 27-2 since we arent trying to reach 30, but 25 in this case.

So basically you tricked everyone by saying it should add to 30, when in fact what does 30 have to do with anything? it should have been 25 since that is the new amount they owed, and the only reason they ended up paying 27 instead of 25 was cuz the bellboy swiped 2 of their bucks :)

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