Question : Directions: If A + B means that A is the father of B, A – B means that A is the mother of B, and A × B means that A is the brother of B then which of the following expressions shows that Q is the son of P?

Option 1: P – R × Q

Option 2: Q – P × R

Option 3: P – Q – R

Option 4: P – Q × R

Correct Answer: P – Q × R

Solution : Let's check the given options –
First option: P – R × Q
According to the given expression, the family tree will be as follows –

Here, the quadrilateral represents the male, and the circular figure represents the female. From the above family tree, it is evident that the gender of Q is not definite. Q can either be the son or daughter of P.
Second option: Q – P × R
According to the given expression, the family tree will be as follows –

Here, the quadrilateral represents the male, and the circular figure represents the female. From the above family tree, it is evident that Q is the mother of P.
Third option: P – Q – R
According to the given expression, the family tree will be as follows –

Here, the quadrilateral represents the male, and the circular figure represents the female. From the above family tree, it is evident that Q is the daughter of P.
Fourth option: P – Q × R
According to the given expression, the family tree will be as follows –

Here, the quadrilateral represents the male, and the circular figure represents the female. From the above family tree, it is evident that Q is the son of P.

So, only the fourth option fulfils the relation given in the question. Hence, the fourth option is correct.