Answer:
C.I = 0.7608 ≤ p ≤ 0.8392
Step-by-step explanation:
Given that:
Let consider a random sample n = 400 candidates where 320 residents indicated that they voted for Obama
probability 
= 0.8
Level of significance ∝ = 100 -95%
= 5%
= 0.05
The objective is to develop a 95% confidence interval estimate for the proportion of all Boston residents who voted for Obama.
The confidence internal can be computed as:

where;
=
= 1.960
SO;






= 0.8 - 0.0392 OR 0.8 + 0.0392
= 0.7608 OR 0.8392
Thus; C.I = 0.7608 ≤ p ≤ 0.8392
Answer:
-1.575, or -1 575/1000, or -1 23/40
Step-by-step explanation:
Simplify the problem slightly by prefacing it with " - " as follows:
334
- ----------- = -1.575 = -1 23/40
212
Line CA is a straight line, meaning it adds up to 180°
Line BE splits the line into two supplementary angles, because when the two angles are added together they will equal 180°
Using the rule of supplementary angles, we can then make the equation 3x + 8x + 15 = 180
Now, simplify the equation by combining like terms
11x + 15 = 180
To solve, isolate x
11x + 15 = 180
11x = 165
x = 15
Y=-2/3x + 2
y=3x-2
one because the slopes are different
parallel when a=2
perpendicular when a=-1/2