DRDO Multi tasking staff Model paper 4

1. X is the only daughter of Y’s grandfather’s only son = this implies X and Y are either siblings
(if Y’s father is Y’s grandfather’s son) or cousins (if Y’s mom is Y’s grandfather’s daughter).
2. Y’s grandfather has only one child = this implies Y’s father is Y’s grandfather’s son and hence X and Y are siblings.

Hence X is Y’s sister.