also help find human compatibility.
Ask two participants to secretly write down a number between 1 and 9 on a piece of paper.
Ask participant #1 to subtract his number from 10 and to silently tell you the answer.
Without peeking (face away from participant) ask participant #2 to follow these directions:
Double the number that he/she has chosen.
Multiply by 5
Subtract the answer given to you by participant #1.
Turn around and ask participant #2 for the answer obtained.
Look at the numbers chosen by the two participants...
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