This could be done if the thread is folded (3 folds) where every fold length
is equal. Then cut this combined thread from between.You will get the
required 3 equals parts and 2 equal parts .
Its like :
A: original
-------------------------- 12 cm thread
B: Ready to cut ( In real scenario vertical parts are almost of zero length)
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|
-------
|
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|
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Cut B rite from between.
Thanks
Deepak