Math

The circumference of the Earth is approximately 40,000 kilometers, and someone has just made a metal band that circles the Earth, touching the ground at all locations.
You come along at night, as a practical joke, and add just 10 meters to its length (one hundredth of one kilometer !)
It is now one fourmillionth longer, and sits magically just above the ground at all locations
How far has it risen … could a flea, a rabbit or even a man squeeze underneath it?
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The cold faucet in a bath lets the water in at the rate of 15 litres per minute.
The hot faucet fills the bath at the rate of 10 liters per minute.
The plug hole lets the water out of the bath at the rate of 12 liters per minute.The bath holds a maximum of 520 liters.
I turn both faucets on, but forget to put the plug in. How many minutes does it take for the bath to overflow?
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Peasant John wants to buy new chickens, pigs, and horses. A new chicken costs 50 euro cents, a pig 3 euros, and a horse 10 euros. Peasant John has 100 euros with which he wants to buy exactly 100 animals, but in such a way, that she has at least one of each kind of animal.
How many animals must peasant John buy of each kind?
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Calculate below as fast as you can, using only mental arithmetic (Without pen, paper, or a calculator!).
Take 1000 and add 40.
Add 1000.
Add 30 and then add 1000.
Add 20.
Add 1000 and then add 10.What is the result of this calculation?
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Three men in a cafe order a meal, the total cost of which is $15. They each contribute $5. The waiter takes the money to the chef who recognizes the three as friends and asks the waiter to return $5 to the men.
The waiter is not only poor at mathematics but dishonest and instead of going to the trouble of splitting the $5 between the three he simply gives them $1 each and pockets the remaining $2 for himself.
Now, each of the men effectively paid $4, the total paid is therefore $12. Add the $2 in the waiters pocket and this comes to $14…..where has the other $1 gone from the original $15?
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There are two ropes which are of different length.
Each rope takes 60 minutes to burn completely when set on fire from one end.
You have to measure 45 minutes of time with the help of this ropes.
You cannot fold the ropes to half or tamper any of them.View SolutionSubmit Solution 334 views
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Jacob and John were busily emptying their book shelves from one room to another.
Jacob on his own could have cleared the room in 18 hours.
John also would take 18 hours.
Unfortunately, James was moving the books back into the first room from the second.
He could fill the first room in 36 hours.
How long will it take the three of them to complete the task?
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The temperature rose by the same amount each day.
The average temperature was 2°C and I know it froze on two occasions.
I also know the product of the temperatures was over 500 but below 2,000 and each temperature was an integer.
What were the last 5 temperatures?
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