#9 BAD MATHS

Find out why the relations below are true. 

   0+7 -> 0     6+2 -> 8
   2+4 -> 8     9+1 -> 9
   4+5 -> 9     7+3 -> 3
   5+6 -> 6     5+1 -> 9
According to that 8-1 is ... ?

Correct answer: E

Explanation:

The numbers have to be interpreted as numbers on a digital clock with a seven-segment display. The "equations" show what happens if you are overlaying two of these numbers (switching the lights on). Subtracting then means switching the light off, which results in an "E", see image below.



One very common wrong answer is '3', but the segments for the "1" are always on the right side, so 3 as an answer is definitely wrong.

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