How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

Find the next number in the series.
1 10 24 43 67 ?

Vin Diesel is pulling a theft and has planned to run away with all the cash kept in the safe. But the only way to open the safe is the 13 character password. He has a set of five clues given to him by a trustworthy source.

Exactly two of the below statements are false.
The password is contained within this sentence.
The password is not in this hint.
The password is within only one of these statements.
At least one of the above statements is a lie.

How many words can a pen with half refill write?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

You can see it everyday, But cannot touch it at will. What is it?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?