Correct Address Identified !

How pointed towards the wrong one? 

Since Mr. House was able to run at one house after answers of passer-by, he must have got clear clues from that.

3. Is it square ?
  
First thing is sure that, the number must not be a non-square otherwise Mr.House wouldn't be sure as there are plenty of non-square numbers between 1 to 50. So it must be either 4,9,16,25,36,49. (1 is omitted for a reason)

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1. In which block is it?

Two possible answers here & 2 possible conclusions.

Block 1  :  4,9,16

Block 2  :  25,36,49

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2. Is the number even ?

Now had passer-by  answered Block 1 in 1st question & odd now then Mr. House would have come to know one exact number 9 (that's why 1 omitted here).

Or had he answered Block 2 in 1st question & even now then also Mr. House would have 1 number i.e. 36.

So in both cases, Mr. House would have got 1 fixed number with no point in asking extra question.


That means the passer-by must have told following answers & their possible conclusions are-

Block 1  :  Even  :  Square  :  4,16

Block 2  :  Odd   :  Square  :  25,49

Connect Dots with Straight Lines

Can you connect all nine dots with only four straight lines without losing contact with the paper while drawing? 

Read here how it can be done!

Source 
 

Connected Dots With Straight Lines

What was the challenge? 

This question often asked in personality development training courses. It needs some out of box thinking. In the question, no where it is mentioned that you line can't go beyond 3 dots. But our brain assumes that & try to find the solution according to that only!

The Alphamatic Problem

In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.

   ABCABA 

+

   BBDCAA 

+

   ABEABB 

+ 

   ABDBAA

-------------------

 AAFGBDH

What does the complete addition look like in digits? 

Note : Alphamatic in the title is word derived from Alphabets & Mathematics. In such problems numbers are replaced by alphabets. The challenge is to find the number for each alphabet satisfying given mathematics equation.

Step by step answer is here! 

Source 

Answer Of Alphamatic Problem

Here is question!

 First of all let's write down the equation once again.


   ABCABA 

+

   BBDCAA 

+

   ABEABB 

+ 

   ABDBAA

-------------------

 AAFGBDH

We will refer to places in number from left as a first, second, third...sixth instead of tenth, hundredth, thousandth etc. 

First we need to find if the 5 digits of first number itself i.e. ABCAB are carries forwarded from previous place.  

From the addition of variable from first place, we get,

3A + B  = 10A + A ........(1)

B  =  8A              ........(2)

Only numbers satisfying above are A = 1 & B = 8 , but at previous place we have addition of 4 B's. If B = 8, then addition at second place would be 32 with F = 2 & carry 3 which is not equal to A = 1. So A can't be a carry. So we need to modify (2) above as

B + x = 8A .........(2)....Where 'x' is carry forwarded from second place.

If B = 1 or 2 then x = 0 as  at second place we would have F = 4 or 8. In that case, A would be fractional. Some other possible combinations for B, A & x are,

B = 9, x = 3,   8A = 12,

B = 8, x = 3,   8A = 10,

B = 7, x = 2,   8A =  9,

B = 6, x = 2,   8A = 8,

This is the only combination that can make A a whole number. So A = 1, B = 6.

---------------------------------------------------------------------------------------------

From sixth place, we have,

H = 3A + B = 9

---------------------------------------------------------------------------------------------

From fifth place, we have,

D = 2A + 2B  = 14

But it has to be single digit i.e. D = 4 with 1 carry forwarded to next.

---------------------------------------------------------------------------------------------

From fourth place,

B = 2A + B + C + 1  .....1 is carry from last place.

6 = 9 + C

Now C can't be negative hence C + 9 has to be 2 digit number with 6 at last digit.Since addition of 2 single digit numbers never exceeds 18, C + 9 has to be 16.

16 = 9 + C 

gives, C = 7 & carry 1 forwarded to third place.

-------------------------------------------------------------------------------------------

Nightclub Tragedy

An American nightclub called 'The Coconut Grove' had a terrible fire in which over 400 people died. A simple design flaw in the building led to the death toll being so high. Subsequently, regulations were changed to ensure that all public buildings throughout the country eliminated this one detail which proved so deadly.

What was it?


Get here to know what was that! 

Source 

Change In Regulations After Tragedy

What was the tragedy? 

This is based on a true story:

The doors at the Coconut Grove opened inward. In the mad dash to escape the fire, people were crushed against the doors and couldn't pull them open. After the Coconut Grove disaster in 1942, all public buildings had to have doors which opened outward.