Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10

Forwards I am heavy, backward I am not. What am I?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

Find the missing number in the image below.

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?