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
malfutka [58]
3 years ago
7

A laptop producing company also produces laptop batteries, and claims that the batteries

Mathematics
1 answer:
gregori [183]3 years ago
5 0

Answer:

There is enough evidence to support the claim that the batteries power the laptops for significantly less than 4 hours. (P-value = 0).

The null and alternative hypothesis are:

H_0: \mu=4\\\\H_a:\mu< 4

Step-by-step explanation:

<em>The question is incomplete: To test this claim a sample or population standard deviation is needed.</em>

<em>We will estimate that the sample standard deviation is 2 hours, and use a t-test to test that claim.</em>

<em> NOTE (after solving): The difference between the sample mean and the mean of the null hypothesis is big enough to reject the null hypothesis, even when we have a sample standard deviation of 3.5 hours, which can be considered bigger than the maximum standard deviation for the sample.</em>

This is a hypothesis test for the population mean.

The claim is that the batteries power the laptops for significantly less than 4 hours.

Then, the null and alternative hypothesis are:

H_0: \mu=4\\\\H_a:\mu< 4

The significance level is 0.05.

The sample has a size n=500.

The sample mean is M=3.5.

As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=2.

The estimated standard error of the mean is computed using the formula:

s_M=\dfrac{s}{\sqrt{n}}=\dfrac{2}{\sqrt{500}}=0.0894

Then, we can calculate the t-statistic as:

t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{3.5-4}{0.0894}=\dfrac{-0.5}{0.0894}=-5.5902

The degrees of freedom for this sample size are:

df=n-1=500-1=499

This test is a left-tailed test, with 499 degrees of freedom and t=-5.5902, so the P-value for this test is calculated as (using a t-table):

P-value=P(t

As the P-value (0) is smaller than the significance level (0.05), the effect is  significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the batteries power the laptops for significantly less than 4 hours.

You might be interested in
Choose the correct expansions. Click to select the correct answers. Click again to unselect answers. Leave the incorrect answers
Nadusha1986 [10]
<span>(5 x 0.001) 0.172 (1 x 0.1) + (7 x .01) + (2 x 0.001)</span>
3 0
3 years ago
$750 loan 7% a year three years of no payments how much interest are you paying?
Anastaziya [24]

Answer:

$157.50

Step-by-step explanation:

First, converting R percent to r a decimal

r = R/100 = 7%/100 = 0.07 per year,

then, solving our equation

I = 750 × 0.07 × 3 = 157.5

I = $ 157.50

The simple interest accumulated

on a principal of $ 750.00

at a rate of 7% per year

for 3 years is $ 157.50.

5 0
2 years ago
At BYU-Idaho there has been a lot of interest in the performance of students in online classes. Generally, administrators are in
blondinia [14]

Answer:

d. Yes, all of the expected counts are greater than or equal to 5

Step-by-step explanation:

Yes, the requirements satisfied to conduct a hypothesis test and all of the expected counts are greater than or equal to 5.

6 0
3 years ago
A bakery sells 5 apple muffins for every 2 bran muffins sold. which table shows this ratio?
shepuryov [24]
The answer to this question is the graph B

6 0
3 years ago
Read 2 more answers
Three integers between -4 and 0
balu736 [363]
Integers between -4 and 0 are : -3, -2, and -1
7 0
3 years ago
Read 2 more answers
Other questions:
  • *use a 2 proof column to answer*
    10·1 answer
  • Write a linear function whose slope is -4 and y-intercept is -5. Explain what these values mean in the equation
    15·1 answer
  • What is -7/2(-7/2x+1)=413/8
    8·2 answers
  • Definition: The ______ place is the place two to the left of the decimal point in a number.
    13·2 answers
  • What is the measure of a single interior angle in a 16-gon?
    9·1 answer
  • Is -51/5 rational or irrrational
    14·1 answer
  • Your 3rd quarter final will be in April. The test will be 100 points total and contain 35 questions.
    8·1 answer
  • 1. Which polynomial is NOT in standard form?
    11·1 answer
  • Determine the range of the following graph:
    13·1 answer
  • What is the answer, I need this for a geometry assignment.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!