For this case we have by definition, that the sum of the exterior angles of a polygon is equal to 360 degrees, only when considering only one exterior angle for each vertex of the polygon, regardless of the number of sides it possesses. That said we have to:
The external angle of a regular polygon is given by:
Where:
n: It is the number of sides of the polygon
Then, for a nonagon each exterior angle will measure:
Answer:
40 degrees each exterior angle
360 degrees the sum
Answer:
A score of 314 is needed to be in the top 25% of students who take this exam.
Step-by-step explanation:
We are given that one of the tests provided by the NAEP assesses the reading skills of twelfth-grade students. In recent years, the national mean score was 289 and the standard deviation was 37.
Let X = <u><em>scores of the tests provided by the NAEP</em></u>
The z-score probability distribution for the normal distribution is given by;
Z = ~ N(0,1)
where, = national mean score = 289
= standard deviation = 37
Now, we have to find how high a score is needed to be in the top 25% of students who take this exam, that means;
P(X > x) = 0.25 {where x is the required score}
P( >
) = 0.25
P(Z > ) = 0.25
In the z table, the critial value of z that represents the top 25% of the area is given as 0.6745, that is;
x = 289 + 24.96 = 313.96 ≈ 314
Hence, a score of 314 is needed to be in the top 25% of students who take this exam.