HOW TO SOLVE HARD AND IMPOSSIBLE PUZZLES PART 2

 we are going to discuss some of the puzzles, challenges or brain teaser which are viral in social media such as Face book ,whats app and twitter    etc. which are based on Mathematics directly or indirectly . You have seen such types of puzzles mentioned 99.9% Fail , Solve if you are genius like this........

Let us try to discuss and solve them. 

PUZZLE # 1

Which number should replace the ?

  4 ,  9 ,  19  ,  39  , 79   ?

when we subtract   4 from  9  we get   5 i.e     9 -  4  =  5 

when we subtract   9 from 19 we get 10 i.e   19 -  9  = 10 

when we subtract 19 from 39 we get 20 i.e.  39 - 19 = 20

when we subtract 39 from 79 we get 40 i.e.  79 - 39 = 40

Now analyse the trends of answers ,we are getting double of the previous number as a result every time .Similarly if we follow the same trend from 79 to next term ,then we shall get 80 as answer. So to get 80 as answer "Add 80 to 79 to get 159 ". when we subtract 79 from 159 ,we get the double of the previous result .

So final answer is  159 - 79 = 80.

  4 ,  9 ,  19  ,  39  , 79  , 159

 Therefore  " ? " will replace 159 as Answer.

PUZZLE # 2

But before we proceed to discuss the Puzzle-1, let us discuss some of the necessary keywords/definitions which have been used in  it.

Even Number

When any Number is divisible by  2 then that number is called An Even number. If we take 2, 16, 84, 22, 20, 100 etc then they are Even Numbers as they can be divided by 2.

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Odd Number

When any number is NOT divisible by  2 then that number is called An ODD number .If we take 21, 15, 49, 21, 57, 101 etc then they are Odd  Numbers as they can NOT  be divided by 2.

Multiple of 3 

An number which is divisible by 3 or which comes in the  table of 3 is called  multiple of 3. if we take 57, 102, 69, 9, 6, 21, 39 etc numbers , as these numbers comes in the table of 3 or these are divisible by 3 , so they are Multiple of 3.

Prime Number

Any number which has only two Factors 1 and the numbers itself is called Prime number. 1 is not the the prime number, 2 ( It is the 1st prime number ) , 3, 5, 7, 11, 13, 17, 19, 23  etc  are examples of Prime numbers as these numbers have only two factors 1 and the number itself.

Square Number

Any number whose square root is a Natural  number is called square Number . such as  1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144 etc.

 Factors of 360

All those numbers which can divide 360 are called factors of 360 .Here We can take such numbers as 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 18, 36 etc

How to Solve 

Have you still not visited "HOW TO SOLVE HARD AND IMPOSSIBLE PUZZLES  PART 1"

PUZZLE # 3

When we multiply   2   with  4,  we get     8
When we multiply   3   with  6,  we get    18
When we multiply   4   with  8,  we get    32
When we multiply   5   with 10, we get    50
When we multiply   6   with 12, we get    72
When we multiply   7   with 14, we get    98
When we multiply   8   with 16, we get    128
When we multiply   9   with 18, we get    162
When we multiply  10  with 20, we get    200

Analyse the Answers above  , we get  4, 6, 8, 10, 12, 14, 16, 18 and 20. Is there any relation between them. Of course, Because every answer is 2 more than the previous Answer. So Last number  should be 200. so in order to get answer 200 we have to multiply  20 with 10.

So       If 2  =  8  

               3  = 18 

               4  = 32

               5  = 50 
               6  = 72  
               7  = 84
               8  = 128
               9  = 172 
              10 = 200 

Then    10 = 200

In order to get any number any of any term  based upon this trends we can use the formula  2n² , where "n "  is the number appearing on left side of the Puzzle.

So Final Answer will be 200

Here is the Solution of the Puzzle asked in "HOW TO SOLVE HARD AND IMPOSSIBLE PUZZLES PART 3" as follows.

There are two numbers 'a' and 'b' in 1st and 2nd columns then 3rd column has been  occupied by their combination as follows

a*b = (a²  + b² ) - 1,

1*3 = (1²  + 3² ) - 1 = ( 1 +   9) -1  = 10 - 1 =  9

3*4 = (3²  + 4² ) - 1 = ( 9 + 16) -1  = 25 - 1 = 24

2*5 = (2²  + 5² ) - 1 = ( 4 + 25) -1  = 29 - 1 = 28

4*5 = (4²  + 5² ) - 1 = (16 + 25) -1 = 41 - 1 = 40

So 40 will replace  ?  in this puzzle   

Conclusion

Thanks for devoting your valuable time for this post  "How   to solve various Hard and impossible puzzles ,Quizzes ,  Brain Teasers and challenges " of my blog . If you liked this this blog/post,  Do Follow me on my blog and share this post with your friends . We shall meet again   in next post with solutions of most interesting and mind blowing puzzles ,till then Good Bye.