6
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IF

7 - 3 = 10124 6 + 3 = 3279 5 – 2 = 763 11 + 2 = 92613 

Then,

15 - 3 =?  

Any ideas ? I dont know how I am supposed to go about solving puzzles like this one ? is there any strategy ? any algorithm ?

  • 0
    It reminds me of a puzzle where you had to count the number of edges. So $a = b \not \Leftrightarrow b = a$ as you apply a function `getNumberOfEdges` to the left. So (if this was handwriting) 1 = 1, 2 = 1, 3 = 0, 4 =1, 5 = 2, 13 = 1, ...2012-11-30

4 Answers 4

9

This is all I can come up with:

1: Do the operation, the answer to that will be placed on the far right:

$ \begin{align} 7-3 &= 4 \\ 6 + 3 &=9 \\ 5-2 &= 3 \\ 11 + 2 &= 13 \end{align}$

2: Take the solution from above, multiply by the second digit in the original expression. Place it to the left of the answer we got in 1.:

$ \begin{align} 4\cdot 3 &= 12 \\ 9\cdot 3&=27 \\ 3\cdot 2&= 6 \\ 13 \cdot 2 &= 26 \end{align}$

So, we have

$ \begin{align} 124 \\ 279 \\ 63 \\ 2613 \end{align}$

3: If the original operation was addition, subtract, and vice versa. Stick this number to the left of the concatenated solutions to 1 and 2:

$ \begin{align} 7+3 &= 10 \\ 6 - 3 &=3 \\ 5+2 &= 7 \\ 11 - 2 &= 9 \end{align}$

Thus, we have

$ \begin{align} 10124 \\ 3279 \\ 763 \\ 92613 \end{align}$

  • 0
    You were 3 mins behind Thomas's answer, but i guess it took you more than 3 mins to format this answer. Hence selected your answer cos it was the fastest.2011-11-24
8

It would be $15-3 = 183612$. Answers are $(\text{opposite operation})(\text{answer} \times\text{second operand})(\text{actual computation})$

6

WARNING: full answer

Note that 7 + 3 = 10, (7-3)*3 = 12, 7 - 3 = 4 Concatenate to get 10124

For the next one, 6 - 3 = 3, (6+3)*3 = 27, and 6+3 = 9 Concatenate to get 3279

Do a similar process for the other two. Its a weird pattern, but its there. And there isn't a general way to solve stuff like that, its just pattern recognition.

  • 0
    ya, its pattern recognition; and you sir, rock at it !2011-11-24
1

15-3 =?

(15+3)((15-3)*3)(15-3)

183612

  • 4
    Yes, that is what all the other answers have said.2011-11-28