Answer:
96
Step-by-step explanation:
Exterior angles add up to 360
360 - 134-130 = 96
x = 96
In order to have average 80 score from 5 tests, student needs to have 400 points (80%*500=0.8*500=400)
So far he has 63+72+88+91= 314
400-314=86
He needs to get 86 points from the last test.
Since he is obviously getting better at tests, i think he'll manage :)
A + s = 504
s = a + 54
a + (a + 54) = 504
2a + 54 = 504
2a = 504 - 54
2a = 450
a = 450/2
a = 225 <=== adults
a + s = 504
225 + s = 504
s = 504 - 225
s = 279 <=== students