A + B means ‘B is the brother of A’;
A − B means ‘A is the mother of B’;
A × B means ‘A is the father of B’;
A ÷ B means ‘A is the son of B’.
If, P + R × T − Q ÷ S + U, then how is S related to R ?

Son-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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