By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

I have thought of a number that is made up by using all the ten digits just once. Here are a few clues for you to guess my number:

First digits is divisible by 1.
First two digits are divisible by 2.
First three digits are divisible by 3.
First four digits are divisible by 4.
First five digits are divisible by 5.
First six digits are divisible by 6.
First seven digits are divisible by 7.
First eight digits are divisible by 8.
First nine digits are divisible by 9.
The number is divisible by 10.

Can you find out the number ?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

Distances from you to certain cities are written below.

BERLIN 200 miles

PARIS 300 miles

ROME 400 milesAMSTERDAM 300 miles

CARDIFF ??? miles

How far should it be to Cardiff ?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

What is the next number in this series?

4,12,84,3612....

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

Can you decipher the below rebus?

PBLUESAISNUERSES

What happened when the wheel was invented?