1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
patriot [66]
3 years ago
10

35. In a simple random sample of 25 high school students, the sample mean of the SAT scores was 1450, and the sample variance wa

s 900. Assume that the data come from a normal distribution , a 95.4 % Confidence interval for the population mean is a. 1450 +/- 180 b. 1450 +/- 18 c. 1450 +/- 12 d. 1450 +/- 360
Mathematics
1 answer:
Tatiana [17]3 years ago
3 0

Answer:

1450-2.0\frac{30}{\sqrt{25}}=1450-12    

1450+2.0\frac{30}{\sqrt{25}}=1450+12    

And the best option would be:

c. 1450 +/- 12

Step-by-step explanation:

Information provided

\bar X=1450 represent the sample mean for the SAT scores

\mu population mean (variable of interest)

s^2 = 900 represent the sample variance given

n=25 represent the sample size  

Solution

The confidence interval for the true mean is given by :

\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}   (1)

The sample deviation would be s=\sqrt{900}= 30

The degrees of freedom are given by:

df=n-1=2-25=24

The Confidence is 0.954 or 95.4%, the value of \alpha=0.046 and \alpha/2 =0.023, assuming that we can use the normal distribution in order to find the quantile the critical value would be z_{\alpha/2} \approx 2.0

The confidence interval would be

1450-2.0\frac{30}{\sqrt{25}}=1450-12    

1450+2.0\frac{30}{\sqrt{25}}=1450+12    

And the best option would be:

c. 1450 +/- 12

You might be interested in
Given: mMEJ=30°,<br> mMFJ= 50°<br> Find: mKL, mMJ
makvit [3.9K]

Applying the angles of intersecting secants theorem, the measures of the arcs are:

m(KL) = 20°; m(MJ) = 80°.

<h3>What is the Angles Intersecting Secants Theorem?</h3>

When two secants intersect and form an angle outside the circle, the measure of the angle formed is half the positive difference of the measures of the intercepted arcs.

Given the following:

  • m∠MEJ = 30°
  • m∠MFJ = 50°

m∠MEJ = 1/2(MJ - KL)

30 = 1/2(MJ - KL)

60 = MJ - KL

KL = MJ - 60

m∠MFJ = 1/2(MJ + KL)

50 = 1/2(MJ + MJ - 60)

100 = 2MJ - 60

2MJ = 100 + 60

2MJ = 160

MJ = 160/2

MJ = 80°

KL = MJ - 60 = 80 - 60

KL = 20°

Thus, applying the angles of intersecting secants theorem, the measures of the arcs are:

m(KL) = 20°; m(MJ) = 80°.

Learn more about angles of intersecting secants theorem on:

brainly.com/question/1626547

4 0
2 years ago
A machine cuts 25 circuit boards every 5 minutes. What is the unit rate of production for the machine?
Sladkaya [172]

Answer:

  • B- 5/1 boards/minutes

Step-by-step explanation:

<u>Unit rate is the number of circuit boards a minute:</u>

  • 25 boards every 5 minutes >>
  • 25/5 boards every 5/5 minutes >>
  • 5/1 boards/minutes

Correct choice is B

3 0
2 years ago
I'm having a hard time with this question so someone help please
bulgar [2K]

Answer:

  7.7 km

Step-by-step explanation:

This question is asking you to find the third side of a triangle in which two sides and an angle not between them are given. The law of sines provides the necessary relationships.

<h3>Law of Sines</h3>

The Law of Sines tells you that triangle side lengths are proportional to the sine of the opposite angle. For this triangle TPJ, the relation is ...

  t/sin(T) = p/sin(P) = j/sin(J)

We are given T=68°, p=5.2 km, t=7.5 km, and we are asked to find the length of j, the TP distance.

<h3>Setup</h3>

We know the sum of angles in a triangle is 180°, and the sine of an angle is equal to the sine of its supplement. This lets us fill in the Law of Sines equation like this:

  7.5/sin(68°) = 5.2/sin(P) = j/sin(68°+P) . . . . . solve for j

<h3>Solution</h3>

This can be solved in two steps. First, we find angle P, then we use that to find length j.

  sin(P) = 5.2/7.5 × sin(68°) ≈ 0.642847

  P = arcsin(0.642847) ≈ 40.0045°

Now, we can find j:

  j = 7.5 × sin(68° +40.0045°)/sin(68°) ≈ 7.693 . . . km

The distance from the tower to the plane is about 7.7 km.

__

<em>Additional comment</em>

We have used T, P, and J to refer to the vertices at the tower, plane, and jet.

The triangle can also be solved using the Law of Cosines. In that case, the missing side will be the solution to a quadratic equation with irrational coefficients.

3 0
2 years ago
Write each fraction as a decimal 5/8
mina [271]

Answer:

0.625

Step-by-step explanation:

Just take a calculator and devide it

5 0
3 years ago
Which equation represents a nonproportional relationship? Which equation represents a nonproportional relationship? A y = 5x B y
kolbaska11 [484]

Answer:

y = 5x + 3 is a nonproportional relationship.

Step-by-step explanation:

We need to find the equation that represents a nonproportional relationship.

If y is directly proportional to x, it would mean that,

y ∝ x

y = kx

Option (b) shows the equation of a line i.e. y=mx+x, where m is slope and x is y-intercept.

Hence, we can say that option (b) represents a nonproportional relationship.

7 0
2 years ago
Read 2 more answers
Other questions:
  • This is an urgent message, help me and get 30 points and brainiest answer!
    15·2 answers
  • 5r^2-38r-16 i must factor by grouping but im very lost
    11·1 answer
  • Paula collected 75 stickers. She shares her stickers with 5 of her friends equally. How many stickers will each get?
    5·1 answer
  • sometime after passing a truck stop 300 miles from the start of her trip Cora's hybrid car ran out of gas assuming that the tank
    13·1 answer
  • := Question Help
    11·1 answer
  • How many cubes are needed to build the base of this structure?<br> A.6<br> B.3<br> C.5<br> D.4
    5·2 answers
  • A data set is shown below. Which is the outlier? 56, 64, 73, 59, 98, 65, 59.
    14·1 answer
  • A team earns 2 points for a win. 1 point for a draw and no point for a loss. The table below shows the points earned by Trinidad
    14·1 answer
  • What is the inverse of the function y-2 = 7x?
    8·1 answer
  • I don’t know if it’s maximum value or minimum value and the answer too
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!