Pointing to a photograph,Vipul said,"She is the daughter of my grandfather's only son." How is Vipul related to the girl in the photograph?

There are six persons $A, B, C, D, E$ and $F$. $C$ is the sister of $F$. $B$ is the brother of $E$'s husband. $D$ is the father of $A$ and grandfather of $F$. There are two fathers,three brothers,and a mother in the group. Who is $E$'s husband?

Lakshmi and Meena are Rohan's wives. Shalini is Meena's step-daughter. How is Lakshmi related to Shalini?

$A + B$ means $A$ is the daughter of $B$. $A - B$ means $A$ is the husband of $B$. $A \times B$ means $A$ is the brother of $B$.
If $P + Q - R$,which of the following is true?

$A + B$ means $A$ is the son of $B$; $A - B$ means $A$ is the wife of $B$; $A \times B$ means $A$ is the brother of $B$; $A \div B$ means $A$ is the mother of $B$; and $A = B$ means $A$ is the sister of $B$.
What does $P = R + Q$ mean?

Five persons namely $P, Q, X, Y,$ and $Z$ are sitting in a park. $P$ is the mother of $X$,who is the wife of $Z$. $Y$ is the brother of $P$,and $Q$ is the husband of $P$. How is $Y$ related to $Q$?