Question

Four interior angles of a pentagon measure 156°, 72°, 98°, and 87°. What is the measure of the final interior angle?

Answer 1

The final interior angle is 127°.  Pentagons' interior angles add up to 540, so you add the ones you know together, subtract the big number from 540, and you have your answer.  

Answer 2

127 because when you add up 156,72,98,87 it equals 413 and for a pentagon's interior angle it equals 540 so 540-413