Can you fill the blank with the correct number?

6 30 870 756030 _____

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Replace the question mark with the correct number, given the pair of numbers exhibits a similar relationship?

? : 3839 :: 11 : 1209

Can you find the six hidden animals in the picture below?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?

A bank customer had $100 in his account. He then made 6 withdrawals. He kept a record of these withdrawals, and the balance remaining in the account, as follows:

Withdrawals Balance left
$50 $50
$25 $25
$10 $15
$8 $7
$5 $2
$2 $0
----- -----
$100 $99

Why are the Totals not tallying?

Count the Triangle in the figure given below:

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

What kind of storm is always in a rush?

A convention is held where all the big logicians are summoned. The master places a band on everyone's forehead. Now all of them can see others bands but can't see his own. Then they are told that there are different colours of bands. All the logicians sit in circle and they are further explained that a bell will ring at regular intervals. The moment when a logician knew the colour of band on his forehead, he will leave at the next bell. If anyone leaves at the wrong bell, he will be disqualified.

The master assures the logicians that the puzzle will not be impossible for anyone of them. How will the logicians manage ?