A − B means ‘A is the sister of B’
A × B means ‘A is the husband of B’;
A ÷ B means ‘A is the son of B’
If, Y × M − T − Z ÷ L × U, then how is U related to Y ?

Mother-in-law

ATQ,

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Please note:

  l   ⇒ Vertical line shown "generation gap".

 =  ⇒ Double lines shown "relation of spouse" 

—  ⇒ Horizontal line shown "relation in same generation other than spouse".

     ⇒ Rectangular box shown " Male".

     ⇒ Circular box shown " Female".

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