Question 1: A triangle has an interior angle of 60°. Calculate the sum of the other two interior angles.

Answer: 120

Question 2: Calculate the sum of interior angles of a quadrilateral.

Answer: 360

Question 3: A pentagon has an interior angle of 108°. What is the total sum of all its interior angles?

Answer: 540

Question 4: Use the sum formula to find the number of sides of a polygon with a total interior angle sum of 1260°.

Answer: 9

Question 5: Construct a hexagon and calculate the measure of each interior angle assuming they are all equal.

Answer: 120

Question 6: A regular octagon has an interior angle of 135°. Calculate its total interior angle sum.

Answer: 1080

Question 7: A polygon has 12 sides. Find the measure of each interior angle if they are all equal.

Answer: 150

Question 8: Explain why a polygon with 5 sides has a total interior angle sum of 540°.

Answer: Using the formula (n-2)×180°, where n=5, so (5-2)×180°=3×180°=540°.

Question 9: A specific polygon's interior angles measure 100°, 110°, 120°, 130°, and 140°. Find the total interior angle sum and the number of sides.

Answer: Total sum=600°, number of sides=4 (quadrilateral).

Question 10: A polygon has 15 sides. What is the measure of each interior angle if all are equal?

Answer: 156

Question 11: Identify and correct the mistake: A pentagon's total interior angles are calculated as 5×180° = 900°.

Answer: Incorrect. The correct total is (5-2)×180°=3×180°=540°.

Question 12: A regular dodecagon has interior angles measuring 150° each. Verify whether this is correct and explain your reasoning.

Answer: Total interior angle sum= (12-2)×180°=1800°, so each angle=1800°/12=150°, which matches the given measure. Therefore, correct.