300, 36 divided by 0.12 (12%) is 300
0.636
Add a 0 then a decimal .you will see the number 70 goes with 6 *11=66
then the remainder will be 4 , add a 0 and you will see the number goes with 3*11= 33 then the remainder will be 7 again add a 0 and multiply 6. You will get your answer.
The interior angles of a 9-agon add up to (9 -2)*180° = 1260°. The sum of the given angles is
.. 1139° +x° = 1260°
.. x = 1260 -1139 = 121
The missing angle measure is 121°.
_____
The supplement of each interior angle is its corresponding exterior angle. The sum of exterior angles of any convex polygon is always 360°. Another way to approach this problem is to add the exterior angles.
