If X × Y means that X is the mother of Y, X - Y means that X is the father of Y, X ÷ Y means that X is the sister of Y, then which of the following expression shows that P is the paternal grandfather of R?

P - Q × R 

After checking all the options, we get the answer from option (iii):

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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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