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
sesenic [268]
3 years ago
10

I need help with this:(

Mathematics
1 answer:
Fudgin [204]3 years ago
6 0

Answer:

94%

Step-by-step explanation:

The whole thing is about averages. Currently the average an 87%, because 85+91+86 = 262. 262/3 = roughly 87%.

Now if she got another score, that would mean it would now be divided by 4 instead of 3. So the equation is:

(262+x)/4 = 89

           *4     *4

____________

262 + x = 356

-262         -262

____________

          x  = 94

You might be interested in
A.) find the test statistic
Arada [10]

Regarding the hypothesis tested in this problem, it is found that:

a) The test statistic is: t = 0.49.

b) The p-value is: 0.6297..

c) The null hypothesis is not rejected, as the p-value is greater than the significance level.

d) It appears that the students are legitimately good at estimating one minute, as the sample does not give enough evidence to reject the null hypothesis.

<h3>What is the test statistic?</h3>

The test statistic of the t-distribution is given by the equation presented as follows:

t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}

In which the variables of the equation are given as follows:

  • \overline{x} is the sample mean.
  • \mu is the value tested at the hypotheses.
  • s is the standard deviation of the sample.
  • n is the sample size.

The value tested at the hypothesis is:

\mu = 60

From the sample, using a calculator, the other parameters are given as follows:

\overline{x} = 62.47, s = 19.2, n = 15

Hence the test statistic is obtained as follows:

t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}

t = \frac{62.47 - 60}{\frac{19.2}{\sqrt{15}}}

t = 0.49.

<h3>What are the p-value and the conclusion?</h3>

The p-value is obtained using a t-distribution calculator, with a two-tailed test, as we are testing if the mean is different a value, in this case 60, with:

  • 15 - 1 = 14 df, as the number of degrees of freedom is one less than the sample size.
  • t = 0.49, as obtained above.

Hence the p-value is of 0.6297.

Since the p-value is greater than the significance level of 0.01, the null hypothesis is not rejected, attesting to the ability of the students to estimate one minute.

More can be learned about the test of an hypothesis at brainly.com/question/13873630

#SPJ1

5 0
1 year ago
What is the constant rate of change shown in the graph?
AnnyKZ [126]

Answer:

10

Step-by-step explanation:

For every lawn mowed, the amount earned increases by 10 dollars

8 0
2 years ago
I
iren2701 [21]

Answer:

The distance between points A and B is 13

Step-by-step explanation:

We need to find distance between points A and B

Looking at the graph,

Point A : (2,6) and Point B: (-3,-6)

We need to find the distance between these points.

The formula used is: Distance=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2} \\

We have Points A : (2,6) and  B: (-3,-6)

So, x_1=2, y_1=6, x_2=-3, y_2=-6

Putting values in formula and finding distance

Distance=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2} \\\\Distance=\sqrt{(-3-2)^2+(-6-6)^2} \\Distance=\sqrt{(-5)^2+(-12)^2} \\Distance=\sqrt{25+144} \\Distance =\sqrt{169}\\Distance = 13

So, the distance between points A and B is 13

6 0
3 years ago
Find the exact value of Cos 240 degrees without a calculator. Show your work!
VMariaS [17]

it equals <span>(−<span>12</span>)</span> because <span><span>cos<span>(<span>60∘</span>)</span></span>=<span>12</span></span>

Explanation:

The reference angle for <span>240∘</span> is <span>60∘</span> (since <span><span>240∘</span>=<span>180∘</span>+<span>60∘</span></span>)

<span>60∘</span> is an angle of one of the standard triangles with 
<span><span>cos<span>(<span>60∘</span>)</span></span>=<span>12</span></span>

<span>240∘</span> is in the 3rd quadrant so (either by CAST or noting that the "x-side" of the associate triangle is negative)
<span><span>cos<span>(<span>240∘</span>)</span></span>=−<span>cos<span>(<span>60∘</span>)</span></span></span>

<span><span>cos<span>(<span>240∘</span>)</span></span>=−<span><span>12</span></span></span>

6 0
3 years ago
F(x) 3x^4-4x^2-3<br> Is this function odd?
Karo-lina-s [1.5K]

Answer:

No.

Step-by-step explanation:

f(x) = 3x^4-4x^2-3

If a function is odd then  f(-x) = -f(x) for all values of x.

Here f(-x) = 3(-x)^4 - 4(-x)^2 - 3

= 3x^4 - 4x^2 - 3

So f(-x) = f(x) which makes it even.

8 0
2 years ago
Other questions:
  • Apples are on sale for $3.12 per kilogram
    15·1 answer
  • 70 cm is what percent of a meter?
    13·2 answers
  • You order a pizza for dinner.
    12·1 answer
  • What´s the answer to this expression 6/2(2+1)
    10·2 answers
  • 18= c+5/3 solve for c please
    8·2 answers
  • Five trucks are to be transported on a ship. Each one weighs 3200 kg and comes
    9·1 answer
  • Sole the following problems by setting up a proportion, then solving by cross multiplying. if possible, set up the proportion as
    11·1 answer
  • For the function f(x)=13x, as x gets bigger, does f(x) increase or decrease?
    10·2 answers
  • What is this reference:wenlocktoad-sama
    11·1 answer
  • Which of the sets of ordered pairs represents a function? (5 points) A = {(2, −2), (5, −5), (−2, 2), (−5, 5)} B = {(4, 2), (4, −
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!