What has many keys but can’t open a single lock?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

I have eight fingers and two thumbs but I do not live. What Am I?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

What is the word or phrase?

The answer I give is yes, but what I mean is no. What was the question?

Count the squares in the matchstick puzzle below?

Find the value of "?" in the ball picture Riddle below:

Pronounced as 1 letter, And written with 3, 2 letters there are, and 2 only in me. I’m double, I’m single, I’m black blue and grey, I’m read from both ends, and the same either way. What am I?