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
Feliz [49]
3 years ago
5

In the beginning of the study, a randomly selected group of 121 students scored an average of 252 words per minute on the readin

g speed test. Since the sample size is larger than 30, the cognitive psychologist can assume that the sampling distribution of M
Mathematics
1 answer:
Alborosie3 years ago
5 0

Answer:

Since the sample size is larger than 30, the cognitive psychologist can assume that the sampling distribution of M will be approximately normal.

Step-by-step explanation:

We use the central limit theorem to solve this question.

The Central Limit Theorem estabilishes that, for a random variable X, with mean \mu and standard deviation \sigma, a sample size larger than 30 can be approximated to a normal distribution with mean \mu and standard deviation s = \frac{\sigma}{\sqrt{n}}

So

Since the sample size is larger than 30, the cognitive psychologist can assume that the sampling distribution of M will be approximately normal.

You might be interested in
Daniel dives into a swimming pool. The height of his head is represented by the function h(t) = -8t2 - 28t + 60, where t is the
8_murik_8 [283]
So, h(t) is how far is Daniel's head from the surface of the water, namely the surface itself is when the height is nill, so his head is at the surface and the height of it is just 0, thus h(t)  = 0.  Namely, what is "t" when h(t) is 0?

\bf h(t)=-8t^2-28t+60\implies \stackrel{h(t)}{0}=-8t^2-28t+60
\\\\\\
0=-2t^2-7t+15\implies 2t^2+7t-15=0\implies (2t+3)(t-5)=0
\\\\\\
\begin{cases}
2t+3=0\implies 2t=-3\implies &t=-\frac{3}{2}\\\\
t-5=0\implies &\boxed{t=5}
\end{cases}

clearly the seconds cannot be a negative unit, so is not -3/2.
6 0
3 years ago
Solve the system using either Gaussian elimination with back-substitution or Gauss-Jordan elimination. (If there is no solution,
Gnom [1K]

Answer:

x1=-4/5, x2=18/5 and x3=7/5

Step-by-step explanation:

\left[\begin{array}{ccc|c}1&0&-3&-5\\3&1&2&4\\2&2&1&7\end{array}\right]

you can do linear combination between the rows:

2nd row=R2-3R1 and 3th row=R3-2R1

\left[\begin{array}{ccc|c}1&0&-3&-5\\0&1&11&19\\0&2&7&17\end{array}\right]

3th row=(3R2-R3)/15

\left[\begin{array}{ccc|c}1&0&-3&-5\\0&1&11&19\\0&0&1&\frac{7}{5} \end{array}\right]

1st row=R1+3R3 and R2-11R3

\left[\begin{array}{ccc|c}1&0&0&-4/5 \\0&1&0&18/5 \\0&0&1&7/5\end{array}\right]

x1=-4/5, x2=18/5 and x3=7/5

6 0
3 years ago
Is 23 and 25 co-primes
MariettaO [177]

Answer:

yes because they have one as a company factor

7 0
4 years ago
Which of these shows the result of using the first equation to substitute for Y in the second equation, then combining like term
Setler [38]

The answer for this question is A

4 0
3 years ago
Read 2 more answers
How do I solve number 15?! Plz help!!!!!
Evgesh-ka [11]

first get all variables on the same side, then use elimination to solve.

x = -3

y = -11

3 0
3 years ago
Other questions:
  • Find the distance between each pair of parallel lines with the given equations y=5x-22 y=5x+4
    5·1 answer
  • In a right triangle, angle is an acute angle and sin angle = 4/9. Evaluate the other five trigonometric functions of angle.
    8·1 answer
  • Match the inequality with its line graph.
    11·1 answer
  • For the standard normal probability distribution, the area to the left of the mean is
    10·1 answer
  • Need correct answer ASAP please
    8·2 answers
  • Please help. I'm trying to help my son with this and I'm so confused.
    14·1 answer
  • Sue solved an equation incorrectly, as shown below:
    5·1 answer
  • Any Simple way to learn mathematics formula ?​
    8·2 answers
  • The equation of a line is y = 3x - 6
    11·2 answers
  • Hlo preparation for exam help with this question?? °_*!
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!