CBSE Class 8 Mathematics Understanding Quadrilaterals Assignments Set 09

Question. Find the angle sum of a convex polygon if the number of sides are
(i) 10
(ii) 7
(iii) 8
Answer: (i) \( 1440^\circ \), (ii) \( 900^\circ \), (iii) \( 1080^\circ \)

Question. Name of a regular polygon with the number of sides are
(i) 10
(ii) 8
(iii) 6
Answer: (i) Decagon, (ii) Octagon, (iii) Hexagon

Question. The Sum of the Exterior angles of any polygon of any no. of sides is ________ and Sum of all interior angles of a polygon is ___________
Answer: \( 360^\circ \) and \( (n-2)180^\circ \)

Question. Find the number of sides of a regular polygon whose each exterior angle is
(i) \( 45^\circ \)
(ii) \( 60^\circ \)
Answer: (i) 8, (ii) 6

Question. Find the number of sides of a regular polygon whose each interior angle is
(i) \( 170^\circ \)
(ii) \( 165^\circ \)
Answer: (i) 36, (ii) 24

Question. Name the polygon if its sides are
(i) 20
(ii) 18
(iii) 16
Answer: (i) 20 gon, (ii) 18 gon, (iii) 16 gon

Question. How many sides does a regular polygon have if each of its exterior angles measures \( 40^\circ \)?
Answer: 9

Question. How many sides does a regular polygon have if each of its interior angles is \( 168^\circ \)?
Answer: 30

Question. Find the sum of the angles of a convex polygon of
(i) 6 sides
(ii) 16 sides
Answer: (i) \( 720^\circ \), (ii) \( 2520^\circ \)

Question. Three angles of a quadrilateral are in the ratio \( 4 : 5 : 3 \). The difference of the least and the greatest of these angles is \( 42^\circ \). Find the angles of the quadrilateral.
Answer: \( 84^\circ \), \( 105^\circ \), \( 63^\circ \) and \( 108^\circ \)