Understanding Elementary Shapes Test - 4

(i) All angles of rectangles are 90°.
This statement is correct because a rectangle has four right angles.

(ii) Trapezium has two pairs of opposite parallel sides.
This statement is incorrect because trapezium has only one pair of opposite parallel sides.

(iii) Opposite angles in rhombus are equal.
This statement is correct because a rhombus is a flat shape with 4 equal straight sides. Opposite sides are parallel and opposite angles are equal.

(iv) Square has all 4 equal sides.
This statement is correct as we know that square is a geometric shape that belongs to the quadrilateral family because it has 4 sides. The 4 sides are of same length and are parallel to each other.

(I) All sides of a parallelogram are of different length.
This statement is incorrect because a parallelogram is a simple quadrilateral with two pairs of parallel sides. The opposite or facing sides of a parallelogram are of equal length and the opposite angles of a parallelogram are of equal measure.

(II) All sides of a rhombus are equal. This statement is correct. A rhombus is a flat shape with 4 equal straight sides and its diagonals are perpendicular to each other.

(III) Rectangle is not a parallelogram.
This statement is incorrect because a rectangle is considered a special case of a parallelogram because a parallelogram is a quadrilateral with 2 pairs of opposite, equal and parallel sides. A rectangle is a quadrilateral with 2 pairs of opposite, equal and parallel sides, but also forms right angles between adjacent sides.

(IV) A parallelogram has no obtuse angle.
This statement is incorrect because as adjacent angles of a parallelogram are supplementary and opposite angles are equal, if one angle is obtuse, adjacent angle would be acute and opposite angle would be obtuse. Hence, a parallelogram can have no more than two obtuse angles.