If eleven plus two equals one, what does nine plus five equal?

How many times can you subtract the number two from the number fifty?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

It's a test that will check your IQ.

Suppose you have one 11 minute hourglass and one 13 minute hourglass.

Can you measure exactly fifteen minutes using them ?

I am first found in caves, now prolific online; I am a depiction, a drawing, a symbol, or sign. I will convey whichever mood you could wish; or for that matter, a fist, flask, or fish. What am I?

what one word does the below rebus identifies?

Who always enjoys poor health?

Three fair coins are tossed in the air and they land with heads up. Can you calculate the chances that when they are tossed again, two coins will again land with heads up?