Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not rounded numerals equals 24.

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?

Can you write down eight eights so that they add up to one thousand?

In a stable, there are men and horses. In all, there are 22 heads and 72 feet. How many men and how many horses are in the stable

You have a roll of cloth 1km long. You have a machine which cuts this roll into pieces of 10-meter-long cloth.

How long would it take for the machine to cut the roll if each cut took 4 secs?

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?