Combination of pieces on Chess board

Puzzle # 10

How many ways are there to arrange the sixteen black or white pieces of a standard international chess set on the first two rows of the board?

• Each square can hold only one chess piece
• All eight Pawns are identical
• Similarly each rook, knight and bishop are identical to its pair.

What could be the possible combinations to arrange the chess pieces on chess board?

Find Total Number of Zeroes

Puzzle # 9

A certain street has 500 buildings. A sign-maker is contracted to number the buildings from 1 to 500. Agreement was made such that contractor will be given with an dollar amount of total Zeroes, that he used to number the buildings?

• Contractor follows some special Convention to earn more amount of dollars

What could be the Count of Zeroes used by contractor ? 
What is the convention followed to gain more dollar amount?

Car on a wild stormy Night

Puzzle # 8

You are driving down the road in your car on a wild, stormy night, when you pass by a bus stop and you saw three people waiting for the bus:

• An old lady who looks as if she is about to die.
• An old friend who once saved your life.
• The perfect partner you have been dreaming about.

Knowing that there can only be one passenger in your car, whom would you choose?

Help Frogs to reach their Destination

Puzzle # 7

There are 2 sets of frogs which need to cross over the other frogs coming in opposite direction to reach their destinations. Each Set has 3 Frogs coming in opposite direction as shown below. 

• Frog can directly jump over a vacant stone only, if vacant stone is immediate next to him.
• Frogs can jump over other frog immediately coming opposite to him to land on vacant stone.
• Frogs can travel only in the faced direction. Back and forth is not possible.

3 Light Bulbs and its Switches

Puzzle # 6
There is a house and a store room is located far away from house. There are 3 Incandescent bulbs arranged in store room. Three Switches to control these bulbs are located in house. Need to identify the correct switch and bulb only visiting store room once. Conditions are as below:

• Each switch can be made On/Off to make the respective bulb glow.
• Only One bulb should glow at a time.
• Emitted light rays are not visible outside the store room, when switched on the bulb.
• All the bulbs are in Good condition.

People to cross River in a Boat

Puzzle # 5

There are 8 people, who need to cross a river in  single boat. People are 1 Cop, 1 Thief, 1 Man and his 2 Daughters, 1 Women and her 2 sons. As usual the conditions that has to be satisfied while crossing the River are given below:

• When Police man is not on that river bank, Thief will beat all the people available on that river bank.
• When Women is Not on that river bank, Man will beat her 2 sons.
• When Man is Not on that river bank, Woman will beat his 2 daughters.
• Only Two people can travel in the boat at any given time.
• 2 Sons and 2 daughters doesn't know to drive the boat.

No one should beat anyone and satisfying above conditions every one should reach other side of river bank safely !! How ?

Identify Odd one with Electronic Balance

Puzzle # 4
There are 10 containers and each container has 10 marbles. Unfortunately one of the container has a wrong set up of marbles which turns out to be over weight when compare to other containers.

How to identify the wrong container that has different set of marbles using Electronic balance? More constraints and hints are given below :

• Electronic balance should be used only one time.
• 10 containers look alike, each container has definite 10 marbles.
• In one container wrong set of marbles are placed which turn out to be overweight.
• All marbles inside any container are same in weight i.e., If Nine valid container has 10 marbles and each marble weigh x grams. In misplaced container has 10 marbles and each marble inside that container weigh y grams (y > x).