Question:
Which of the following can be four interior angles of a quadrilateral?
(a) 140o, 40o, 20o, 160o
(b) 270o, 150o, 30o, 20o
(c) 40o, 70o, 90o, 60o
(d) 110o, 40o, 30o, 180o
Solution:
(a) 140o, 40o, 20o, 160o
We know that sum of interior angles of quadrilaterals is 360o.
So, 140o + 40o + 20o + 160o = 360o
In option (d) has angle sum equal to 360o, but one angle is 180o if it is considered then the quadrilateral becomes a triangle.