Given that X= quadrilateral, Y= triangle, Z= trapezium, which of
the following is correct?
(A) Y is a subset of Z
(B) X is a subset of Z
(C) Y is a subset of X
(D) Z is a subset of X
answer is (D), y--> i thought Z is a proper subset of X.
My reasoning is all trapeziums are quadrilaterals, but not all
quadrilaterals are trapeziums.
hence, trapezium is a member of quadrilateral but quadrilateral
has more elements than just trapeziums, quadrilaterals can be
square, rhombus etc