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Rudik [331]
3 years ago
13

In a random sample of 400 residents of Boston, 320 residents indicated that they voted for Obama in the last presidential electi

on. Develop a 95% confidence interval estimate for the proportion of all Boston residents who voted for Obama.
Mathematics
1 answer:
coldgirl [10]3 years ago
3 0

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 \hat p = \dfrac{320}{400}

= 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:

=\hat p  \pm Z_{\alpha/2} \sqrt{\dfrac{ p(1-p)}{n } }

where;

Z_{0.05/2} = Z_{0.025} = 1.960

SO;

=0.8  \pm 1.960 \sqrt{\dfrac{ 0.8(1-0.8)}{400 } }

=0.8  \pm 1.960 \sqrt{\dfrac{ 0.8(0.2)}{400 } }

=0.8  \pm 1.960 \sqrt{\dfrac{ 0.16}{400 } }

=0.8  \pm 1.960 \sqrt{4 \times 10^{-4}}

=0.8  \pm 1.960 \times 0.02}

=0.8  \pm 0.0392

= 0.8 - 0.0392     OR   0.8 + 0.0392  

= 0.7608    OR    0.8392

Thus; C.I =  0.7608   ≤ p ≤   0.8392

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Answer:

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Step-by-step explanation:

It is given that,

Length of the sash when it is completed = 8 feet

Joseph wants to add a diamond shape every 0.4 feet along the sash.

We need to find no of diamonds the sash have when it is completed. It can be calculated by dividing total length by 0.4 feet. As a result,

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2 years ago
PLEASE I NEED HELP ASAP
Annette [7]

The coordinates of the vertex that A maps to after Daniel's reflections are (3, 4) and the coordinates of the vertex that A maps to after Zachary's reflections are (3, 2)

<h3>How to determine the coordinates of the vertex that A maps to after the two reflections?</h3>

From the given figure, the coordinate of the vertex A is represented as:

A = (-5, 2)

<u>The coordinates of the vertex that A maps to after Daniel's reflections</u>

The rule of reflection across the line x = -1 is

(x, y) ⇒ (-x - 2, y)

So, we have:

A' = (5 - 2, 2)

Evaluate the difference

A' = (3, 2)

The rule of reflection across the line y = 2 is

(x, y) ⇒ (x, -y + 4)

So, we have:

A'' = (3, -2 + 4)

Evaluate the difference

A'' = (3, 4)

Hence, the coordinates of the vertex that A maps to after Daniel's reflections are (3, 4)

<u>The coordinates of the vertex that A maps to after Zachary's reflections</u>

The rule of reflection across the line y = 2 is

(x, y) ⇒ (x, -y + 4)

So, we have:

A' = (-5, -2 + 4)

Evaluate the difference

A' = (-5, 2)

The rule of reflection across the line x = -1 is

(x, y) ⇒ (-x - 2, y)

So, we have:

A'' = (5 - 2, 2)

Evaluate the difference

A'' = (3, 2)

Hence, the coordinates of the vertex that A maps to after Zachary's reflections are (3, 2)

Read more about reflection at:

brainly.com/question/4289712

#SPJ1

8 0
1 year ago
Use the figure to answer the questions below.
alina1380 [7]

Answer:

  • parallelogram
  • x = 5
  • 60 units

Step-by-step explanation:

A. Opposite sides are the same length, so the figure is a parallelogram.

__

B. Diagonals of a parallelogram cross at their midpoints, so ...

  9x +3 = 10x -2

  5 = x . . . . . . . . add 2-9x to both sides

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C. The longer side is 12x = 12(5) = 60 . . . . units

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3 years ago
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cestrela7 [59]
The range of a function is the set of numbers used as y-coordinates.

Let's look at the y-coordinates of the points in the graph.
There are points in the graph with all y-coordinates greater than -3.
There are points in the graph with all y-coordinates less then -3.
At exactly -3, there is no point on the graph with that y-coordinate.
We expect the graph to behave as it is shown above 7 and below -7, so the only value excluded from the y-coordinates is -3.

Answer: B. All real numbers except -3
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3 years ago
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olganol [36]

x⁶

look at the picture

l hope that's help you

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