There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

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 ?

It is a 5 letter word if you take away first letter it is something you get from sun, if you remove second letter you will get something to eat, if you remove third letter you get a word you use in pointing at and if you remove the fourth letter you get something to drink. What is it?

Name a key which is hardest to turn.

I can be cracked, made, told, and played. What am I?

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?

There's a day, that comes around once a year.
To celebrate the man, you hold dear.
He gave you life, love and will pick you up if you fall.
When it comes to guys like him, He's the best of all.
Who is he?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

In the image given, you can find several triangles. Can you count them all?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?