What is the next number in this series?

4,12,84,3612....

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 ?

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

Can you count the number of lines in the below picture?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

The below given figure comprises of a pattern through which you can determine the missing letter. Can you push your mind to find the pattern and add the missing letter?

A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

How can one talk without saying a single word?

Complete the following series. It.s very logical:

1, 4, 5, 6, 7, 9, 11, __?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?