Math Riddles

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Train Journey

Train Journey

Mr. Grumper grumbles about bad time-keeping trains like everybody else. On one particular morning he was justified, though.

The train left on time for the one hour journey and it arrived 5 minutes late. However, Mr. Grumper’s watch showed it to be 3 minutes early, so he adjusted his watch by putting it forward 3 minutes. His watch kept time during the day, and on the return journey in the evening the train started on time, according to his watch, and arrived on time, according to the station clock.

If the train traveled 25 percent faster on the return journey than it did on the morning journey, was the station clock fast or slow, and by how much?

The station clock is 3 minutes fast. The morning journey took 65 minutes, and the evening journey therefore took 52 minutes, and the train arrived 57 minutes after it should have left, that is, 3 minutes early.
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30 Cents

30 Cents

How can you make 30 cents out of two coins. One of the coins can not be a quarter.

A quarter and a nickel. Only ONE of the coins cannot be a quarter but a nickel is not a quarter.
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The Missing Dollar

The Missing Dollar

Three friends check into a motel for the night and the clerk tells them the bill is $30, payable in advance. So, they each pay the clerk $10 and go to their room. A few minutes later, the clerk realizes he has made an error and overcharged the trio by $5.

He asks the bellhop to return $5 to the 3 friends who had just checked in.

The bellhop sees this as an opportunity to make $2 as he reasons that the three friends would have a tough time dividing $5 evenly among them; so he decides to tell them that the clerk made a mistake of only $3, giving a dollar back to each of the friends. He pockets the leftover $2 and goes home for the day!

Now, each of the three friends gets a dollar back, thus they each paid $9 for the room which is a total of $27 for the night.

We know the bellhop pocketed $2 and adding that to the $27, you get $29, not $30 which was originally spent.

Where did the other dollar go?

The facts in this riddle are clear: There is an initial $30 charge. It should have been $25, so $5 must be returned and accounted for. $3 is given to the 3 friends, $2 is kept by the bellhop - there you have the $5. The trick to this riddle is that the addition and subtraction are done at the wrong times to misdirect your thinking - and quite successfully for most. Each of the 3 friends did indeed pay $9, not $10, and as far as the friends are concerned, they paid $27 for the night. But we know that the clerk will tell us that they were charged only $25 and when you add the $3 returned with the $2 kept by the bellhop, you come up with $30.
Reveal Answer

Five Zeros

Five Zeros

How can you make 120 using  five zeros?

(0!+0!+0!+0!+0!)! = 120
Check a calculator to verify!
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