#201 - Challenging Logic Puzzle

In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However, you know that the fake coin is lighter than the rest, and in front of you is a balance scale. What is the least number of weightings you can use to find the counterfeit coin?

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The answer is 2. First, divide the coins into 3 equal piles. Place a pile on each side of the scale, leaving the remaining pile of 3 coins off the scale. If the scale does not tip, you know that the 6 coins on the scale are legitimate, and the counterfeit is in the pile in front of you. If the scale does tip, you know the counterfeit is in the pile on the side of the scale that raised up. Either way, put the 6 legitimate coins aside. Having only 3 coins left, put a coin on each side of the scale, leaving the third in front of you. The same process of elimination will find the counterfeit coin.

#202 - Weighing Balance Puzzle

You can place weights on both side of weighing balance and you need to measure all weights between 1 and 1000. For example if you have weights 1 and 3,now you can measure 1,3 and 4 like earlier case, and also you can measure 2,by placing 3 on one side and 1 on the side which contain the substance to be weighed. So question again is how many minimum weights and of what denominations you need to measure all weights from 1kg to 1000kg.

Weighing Balance Puzzle
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For this answer is 3^0, 3^1, 3^2... That is 1,3,9,27,81,243 and 729.

#203 - Funny Logic Riddle

A woman shoots her husband.
Then she holds him under water for over 5 minutes.
Finally, she hangs him.
But 5 minutes later they both go out together and enjoy a wonderful dinner together.
How can this be?

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The woman was a photographer. She shot a picture of her husband, developed it, and hung it up to dry.

#204 - Lateral Thinking Question

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

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The surgeon is the boy's mother

#205 - Decode This Message

Decode The Message

carrot fiasco nephew spring rabbit
sonata tailor bureau legacy corona
travel bikini object happen soften
picnic option waited effigy adverb
report accuse animal shriek esteem
oyster

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Starting with the first two words, Take the first and last letters, reading from left to right. Example: Carrot fiascO "from these pairs" the message is as follows:

CONGRATULATIONS CODE BREAKER

#206 - Trick Teaser Riddle

Jason decided to give his bike 3 coats of paint. Which coat would go on the first?

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The second, as it is the only coat that can go on 'the first' coat.

#207 - CAT EXAM Riddle

There is a shop that reads:
Buy 1 for $1.00
10 for $2.00
100 for $3.00
I needed 913 and still only paid $3.00. How could this be financially viable for the shop-keeper?

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They are numbers for houses and it's $1 per digit.

#208 - Hard Maths Puzzle

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

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The only lockers that remain open are perfect squares (1, 4, 9, 16, etc) because they are the only numbers divisible by an odd number of whole numbers; every factor other than the number's square root is paired up with another. Thus, these lockers will be 'changed' an odd number of times, which means they will be left open. All the other numbers are divisible by an even number of factors and will consequently end up closed.

So the number of open lockers is the number of perfect squares less than or equal to one thousand. These numbers are one squared, two squared, three squared, four squared, and so on, up to thirty one squared. (Thirty two squared is greater than one thousand, and therefore out of range.) So the answer is thirty one.

#209 - Crazy Riddle

Why is it against the law for a man living in Delhi to be buried in Mumbai?

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Because he is still living

#210 - Albert Einstein Cipher Puzzle

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

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You can never solve a problem on the level on which it was created.
Here is the answer key:
A-Z
B-Y
C-X
D-W
E-V
F-U
G-T
H-S
I-R
J-Q
K-P
L-O
M-N
N-M
O-L
P-K
Q-J
R-I
S-H
T-G
U-F
V-E
W-D
X-C
Y-B
Z-A