Solution:

Take 10 number of cards in a new deck and change their face direction. For example- You create a new deck of 10 cards and out of 10, 3 faces up in the new deck. So remaining 7 faces up are in the old deck. But hey! while creating the new deck you reversed the face direction of new cards. So actually the 3 cards which were facing up are actually face down in the new deck while 7 faces up.

Solution:

Solution is shown in image below

Solution:

I Am stone.

Explanation:
Stone is 5 letter word. if remove word one(not 1 letter) we will get st.

Solution:

The thief is the Pakistani guy. It is because the flag of Japan looks same when upside down and no one can tell if it is upside down. So, he was telling a lie.

Solution:

30

Explanation:
It's very difficult to count an actual number of balls but it can be counted mathematically as illustrated below.

Balls in lowest level most level, say level 1 : 4 * 4 = 16
Level2 => 3 * 3 = 9
Level3 => 2 * 2 = 4
Leve4 => 1

Summing up 16+9+4+1 = 30.

Solution:

Solution is done below.

(0! + 0! + 0! )! =6
(1! + 1! + 1! )! =6
2 + 2 + 2 = 6
3 * 3 - 3 = 6
4 + 4 -sqrt(4) = 6
5 + 5 / 5 = 6
6 + 6 - 6 = 6
7 - 7 / 7 =6
8 - sqrt(sqrt(8+8) = 6
(9 + 9) / sqrt(9) = 6

Solution:

3012

Explanation:
A)
Five Commando alloted 5 room each, Number of rooms = 5 * 5 = 25

Number of huge Tiger = 25 * 5 = 125
Number of small Tigers = 125 * 5 = 625
Total tigers = 625 + 125 = 750

Number of legs of tigers = 750 * 4 = 3000 ..............................(1)

B)
There are 5 soldiers =>
Number of legs of soldiers = 5*2 = 10 .......................(2)

C)
Your leg = 2 ............(3)

Summing all , 3000 + 10 + 2 = 3012

Solution:

301

= Explanation =
Time1 : When there are two pirates, 301/2 => remainder 1
Time2 : When there are three pirates, 301/3 => remainder 1
Time3 : When there are three pirates, 301/4 => remainder 1
Time4 : When there are three pirates, 301/5 => remainder 1
Time5 : When there are three pirates, 301/6 => remainder 1
Time6 : When there are three pirates, 301/7 => remainder 0

Solution:

The Lady sitting in the chair has the detector attached to the back of her blouse.

Solution:

To add commutative balance in the puzzle above is mistake
You will get this when I show you another way to spend $50.

Spent Balance
5                   45
5                   40
5                   35
5                   30
5                   25
5                   20
5                   15
5                   10
5                   05
5                   00
=========
50                   225

The numbers i choose smartly to confuse readers.