A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

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?

I am something people love or hate. I change peoples appearances and thoughts. If a person takes care of them self I will go up even higher. To some people I will fool them. To others I am a mystery. Some people might want to try and hide me but I will show. No matter how hard people try I will Never go down. What am I?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

What is full of holes but still holds water?

What occurs twice in a week, once in a year but never in a day?

Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.

How will you do it?

what's the probability of getting a king or a queen from a pack of 52 cards?