Spirit Of Genius

Once Mandar forgot his mother in law's birthday. Obviously, as a universal rule, he got the punishment. His wife ordered, I want you to present gold weighing equal to date of day on which my mother would surprise visit to our home.

Now Mandar went to jeweler & ordered only 5 gold coins of different weights. What are the weights of those gold coins?

This is how he does!

Gold For Every Date Designed Smartly

What was that intellectual puzzle?

On whichever date she visits, he just presents those coins under which 1 is written. For example, if she visits on 25, he would give her coins weighing 16,8 & 1. And if she visits on 18, he would present her coins weighing 16 & 2! Great use of binary number system!

Proof 2+2=5

Proof 2 + 2 = 5

I think this is the misstep!

Equating Negative Number To Positive Numer

Proof : 2 + 2 !=5

Look what is done under square roots in red rectangles. At first, 4 - 9/2 = - 1/2 is squared to 1/4 & at second while taking square root of same 1/4, it's taken as + 1/2. So -1/2 converted to +1/2 by squaring followed by taking square root. This is certainly not 'fair' mathematically!

Actually square root of (5-9/2)^2 should have been - (5-9/2) = - 1/2!

Here is that attempt!

Proof 2 = 1

Can you figure out misstep in above?

Here it is figured out!

How Proof : 2 = 1 is Wrong

What was allowed?

Since a = b, then a - b = 0.

So we can't divide both sides by (a - b) on both sides to eliminate (a -b) since division by 0 is not defined or infinity!

Classic Fallacies, false algebra, dirty maths tricks,

Non-Zero Number Using Only Zeros

The challenge is bringing 120 on other side of = using only 0 s. You are not allowed to use any number from 1 to 9 but allowed to use +, -, x, / .However you can use any number of zeros!

How it could be?

Challenge accepted here!

Non-Zero Output Using Zero Input

What was the challenge?

All you need to use ! here like below.

(0! + 0! + 0! + 0! + 0!)! = 120.

Unfair Loss in Savings of Life

On his 20th birthday, Ajay started depositing Rs.500 in his saving box. His brother Vijay used to withdraw Rs.100 from the same box on his birthday every year. On his 60th birthday, Ajay opens his box & finds only Rs.1000 in it.

How this could be possible?

Ajay & Vijay

This is how it's possible

Having Birthday On Leap Day

What was looking impossible?

Since Ajay celebrates his birthday on 29th February, he used to deposit Rs.500 in saving box once in 4 years. From age 20 to 60, he celebrated only 10 birthdays saving only 500 x 10 = 5000.

But Vijay withdrawing Rs.100 every year means he took 100 x 40 = 4000 so far.

That's why only 5000 - 4000 = 1000 left in the box.

Leap Day birthday affecting life savings

Just To Test Your Common Sense

Below are four (4) questions and a bonus question. You have to answer them instantly. You can't take your time, answer all of them immediately. Okay?

Let's find out just how clever you really are .

Ready?

GO!!!

Question 1 :

You are participating in a race. You overtake the second person. What position are you in?

Question 2 :

If you overtake the last person, then you are...?

Question 3 :

Very tricky math! Note: This must be done in your head only. Do NOT use paper and pencil or a calculator. Try it.

Question 4 :

Mary's father has five daughters: 1. Tana, 2. Tene, 3. Tini, 4. Tono. What is the name of the fifth daughter?

Bonus Question :

There is a mute person who wants to buy a toothbrush. By imitating the action of brushing one's teeth he successfully expresses himself to the shopkeeper and the purchase is done.

Now if there is a blind man who wishes to buy a pair of sunglasses, how should he express himself?

View your results here!

Verify Answers of Common Sense Test

Here is the TEST!

Answer 1: If you answered that you are first, then you are absolutely wrong! If you overtake the second person and you take his place, you are second!

Answer 2: If you answered that you are second to last, then you are wrong again. Tell me, how can you overtake the LAST person!

Answer 3: Did you get 5000? The correct answer is actually 4100.
Don't believe it? Check with your calculator! Today is definitely not your day. Maybe you will get the last question right?

Answer 4: Tunu?
NO! Of course not. Her name is Mary. Read the question again.

Bonus Answer : He just has to open his mouth and ask, so simple

'Sabrina and Samantha' Brain Teaser

Sabrina gave Samantha as many dollars as Samantha started out with. Samantha then gave Sabrina back as much as Sabrina had left. Sabrina then gave Samantha as back as many dollars as Samantha had left, which left Sabrina broke and gave Samantha a total of $80.00.

How much did Sabrina and Samantha have at the beginning of their exchange?

Find here how much!

Initial Amount Sabrina & Samantha had

But what was that?

This could be solved using simultaneous equations but going in reverse makes it easy.

At each stage, one's money is doubled. At last stage, Samantha doubled money to 80 by receiving 40 from Sabrina. So both had 40 before that.

How Sabrina had 40? Since Samantha gave her 20 at previous transaction. So Samantha had 40+20=60 & Sabrina had 20 before this transfer.

And how Samantha had 60? Since she received 30 from Sabrina at previous transfer. So Sabrina had 30+20=50 & Samantha had 30 before the transfer.

Hence at start , Sabrina had 50 & Samantha had 30!

Initially Sabrina had 50 & Samantha had 30!

Probability of Correct Package Labeling

Brad Doe works for a packaging company. One day, he received four separate orders and accidentally mixed up the addresses, so he applied the
address labels at random.

What is the probability that exactly three packages were correctly labeled?

Labeled Packages

Skip to answer!

Common Sense in Finding Probability

Why this question?

Answer is 1!

If three are correctly placed fourth has to be. There are only 4!

Would You Help This Farmer ?

A farmer had 25 cows. To identify easily he numbered them from 1 to 25. Interestingly, each cow produces liters of milk equal to the respective number given. For example, a cow numbered 5 gives 5 liters of milk or a cow numbered 18 produces 18 liters of milk. Now that farmer had 5 sons. Farmer wants to share those 25 cows among his 5 sons with each son getting 5 cows. But he wants to make sure each son would get equal amount of milk.

How should he make 5 groups of cows to distribute among his sons?

Please, Help me!

This is what farmer need to do!

Fair Distribution of Farmer's Cows

What was the interesting?

First let's name 5 sons as A,B,C,D & E. Now look at the image below.

Just collect numbers surrounded by same shapes. If you observe carefully answer, a difference of 4 created at one place which is compensated at other 4. Each son would be getting 65 liters of milk.

Fair Distribution of 25 cows among 5 sons

Fair Distribution of Cows

Man Walking on Moving Escalator

A man can walk up a moving "up" escalator in 30 seconds. He can walk down this moving "up" escalator in 1-1/2 minutes. If his walking pace is the same going upstairs as downstairs, how long would it take him to climb the escalator if it was stationary? How long would it take him to go up the moving escalator if he stood still?

Man walking up & down on moving escalator

Calculated here!

Man on Stationary Escalator

What was asked to calculate?

Let L = length of stair , M = Man's speed & E = Elevator's speed.

Let's remind what we have learned in our school days.

Speed = Distance/Time

i.e.

Distance = Speed x Time

While moving 'up' along with upward moving elevator,

30(M+E) = L ......(1)

While moving 'down' against 'upward' moving elevator, man's speed has to be faster than elevator's speed so that he can reach down at the stair. Otherwise he would never reach down always falling short.

90(M-E) = L .......(2)

From (1) & (2), we get,

30M+30E=90M-90E

60M=120E

M=2E .....(3)

E=M/2 .....(4)

Putting (3) in (1),

45M=L

M=L/45

(Speed=Distance/Time)

Hence man alone needs 45 seconds to climb up that stationary elevator.

Stationary Escalator

Putting (4) in (1), gives,

E=L/90

(Speed=Distance/Time)

So elevator needs 90 seconds to push standing man up.

Solve this Murder case (challenge)

Solve this Murder case (challenge)..

Near Mumbai

A man was found murdered on 9-11-2016 Wednesday afternoon at 12.35 PM in his house...... His wife called police at 3:23 PM.

Police questioned everyone..

Wife: I was sleeping..

Son: I went for movies with my gf

Neighbor: We went for the marriage..

Driver: I went to ATM withdraw cash..

Cook: I went to Wine shop to buy Wine..

Gardener: I was in garden the whole time. I didn't hear anything.
.
Watch Man: I went to my relative's Marriage..

Police arrested the murderer immediately..

Who was it?

Find who was that here!

Murder Mystery Investigation

But what was the case?

Driver was the murderer!

He must be lying as ATMs were closed on 9-11-2016 after note demonetization in India.

Just A Spare Thought...

I always had this concept in my mind but absolutely no idea whether it's possible or not.

We know, light takes 8 minutes 20 seconds to travel from Earth to Sun. So if we are looking at Sun at any time it's 8 minutes 20 seconds old. Now if we place a very high power camera with a great optical zoom at few light years say 10 years from Earth & zoom at Earth then wouldn't it possible to observe what was going on Earth 10 years ago? Wouldn't it be a time machine only difference it's not taking us physically at that time.

I know it would be literally impossible to place such camera but who had thought communications without wires few centuries ago! Just a crazy thought shared.

Make Dog To Look In Opposite

Challenge here is that you need to make dog to look at opposite direction by just moving only 2 match sticks.

Here I moved those!

Now Dog Looking In Opposite

What was the challenge?

Analyse The Pattern

If,

5 + 3 + 2 = 151012

9 + 2 + 4 = 183662

8 + 6 + 3 = 482466

5 + 4 + 5 = 202504.

Then,

7 + 2 + 5 = ??????

Answer is here!

Analysis of The Pattern

Find the question here!

Let's try to put it in mathematical equation,

a + b + C

1. First two digits of answer is product of first two digits a & b i.e. ab.

2. Next two digits of answer are formed by product of first & last digits i.e. a & c = ac.

3. For last two digits of answer, first & last digits are added & then multiplied by second

digit like (a+c) × b = cd. Now the places of digits of results are interchanged as dc.

With the same logic applied,

7 + 2 + 5 = 143542.

Why Do People See The World Differently?

Left Vs Right

This is what I think.....

Fake Test - Perception Psychology.

What was the test?

There are neither 3 or 4 but actually only 2. Front face of middle one is missing. Instead a faces are inserted between 1 & middle also 2 & middle at front end. That's how optical illusion created there!

Reality of Left Vs. Right

How Many Tigers In The Picture?

Count tigers

And here is attempt to count those!

Tigers In Picture Pointed & Counted

There are 15 or may be 16!

What was the task given?

For faces marked with red circle , you need to zoom in.....Few might not count face marked with pink circle while others may claim that face hidden behind the leaves...!

Tigers Pointed

What is The Parking Spot Number?

Parking Spot Number

That's not that much difficult as it seems!

Know The Parking Spot Number

But what was the so simple?

Just rotate the picture 180 degree clockwise!

If you still didn't get it look again & again until you get answer 87!

Parking Spot Number

What Comes Next in Series?

What's next?

1,11,21,1211,111221,?

What's Next?

Here it is found!

Look-And-Say Sequence Based Series

This is what you need to find!

That's called as look - and - say sequence in math. It's all about attaching count sequentially of the number of same digits in previous one to find the next one in sequence.

1. First number in sequence is 1.

2. To find the next one in sequence counting number of same digits in previous & writing the count with that digit. Here 1 appears one time so it's 11.

3. In previous, 1 appears 2 times so here it's 21.

4. In previous, 2 appears once & 1 appears once. Hence , it's 1211!

5. Now here previously 1 appears once, 2 appears once & again 1 appears twice. So next one is 111221.

6. Looking at previous, 1 appears thrice, 2 appears twice & again 1 appears once. So the next one is 312211!

Finding the next in look and based sequence

More info!

In The Search Of Spirit.....

You are an expert on paranormal activity and have been hired to locate a spirit haunting an old resort hotel. Strong signs indicate that the spirit lies behind one of four doors. The inscriptions on each door read as follows:

Door A: It's behind B or C.

Door B: It's behind A or D.

Door C: It's in here.

Door D: It's not in here.

Your psychic powers have told you three of the inscriptions are false, and one is true. Behind which door will you find the spirit?

Finding door behind which spirit is hidden

4 Doors

Find the correct door here!

Source

Psychic Expert Needs Logical Thinking

Clues that psychic expert can use!

Let's believe our psychic powers & remember only 1 inscription can be TRUE & other 3 must be FALSE.

1. If the spirit is really behind the Door A , then both the inscriptions - on Door B & Door D are TRUE.

2. If the spirit is behind the Door B then again 2 inscriptions - one on Door A & Door D are TRUE.

3. If we assume the spirit is behind the Door C then both the inscriptions that are on Door C & Door D are TRUE.

4. So we are only left with the Door D & that's where wanted spirit lies. In this case only inscription on Door B is TRUE & rest of all are FALSE.

And let's not forget to congratulate an expert within us for this wonderful achievement!

Unlock The Lock

Unlock it

It's cracked down here!

Code To Unlock The Lock