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
Zielflug [23.3K]
3 years ago
6

A simple random sample of 20 days in which Parsnip ate seeds was selected, and the mean amount of time it took him to eat the se

eds was 14.5 seconds with a standard deviation of 3.98 seconds. An independent simple random sample of 17 days in which Parsnip ate pellets was selected, and the mean amount of time it took him to eat the pellets was 13.9 seconds with a standard deviation of 4.03 seconds. If appropriate, use this information to calculate and interpret a 90% confidence interval for the difference in the mean amount of time it takes Parsnip to eat seeds and the mean amount of time it takes Parsnip to eat pellets.
Mathematics
1 answer:
bearhunter [10]3 years ago
5 0

Answer:

(14.5-13.9) -1.69 \sqrt{\frac{3.98^2}{20}+ \frac{4.03^2}{17}} = -1.63

(14.5-13.9) +1.69 \sqrt{\frac{3.98^2}{20}+ \frac{4.03^2}{17}} = 2.83

And the confidence interval for this case -1.63 \leq \mu_1 -\mu_2 \leq 2.83

Step-by-step explanation:

We know the following info from the problem

\bar X_1 = 14.5 sample mean for the group 1

s_1 = 3.98 the standard deviation for the group 1

n_1= 20 the sample size for group 1

\bar X_2 = 13.9 sample mean for the group 2

s_1 = 4.03 the standard deviation for the group 2

n_2= 17 the sample size for group 2

We have all the conditions satisifed since we have random samples.

We want to construct a confidence interval for the true difference of means and the correct formula for this case is:

(\bar X_1 -\bar X_2) \pm t_{\alpha/2}\sqrt{\frac{s^2_1}{n_1} +\frac{s^2_2}{n_2}}

The degrees of freedom are given :

df = n_1 +n_2- 2 = 20+17-2=35

The confidence level is 0.9 or 90% and the significance level is \alpha=1-0.9=0.1 and \alpha/2 = 0.05 and the critical value for this case is:

t_{\alpha/2} = 1.69

And replacing the info given we got:

(14.5-13.9) -1.69 \sqrt{\frac{3.98^2}{20}+ \frac{4.03^2}{17}} = -1.63

(14.5-13.9) +1.69 \sqrt{\frac{3.98^2}{20}+ \frac{4.03^2}{17}} = 2.83

And the confidence interval for this case -1.63 \leq \mu_1 -\mu_2 \leq 2.83

You might be interested in
A rectangle has a length of 45 inches less than 4 times its width. if the area of the rectangle is 3325 square inches, find the
Maru [420]

The length of the rectangle is based on its width, so let's call width w and put the length in terms of the width. We are told that the width is 45 less than 4 times the width, so the length is 4w - 45. Area is found by multiplying length times width and we are given the area as 3325. So we will set up length times width and solve for w, which we will then use to solve for l. 3325 = (4w - 45)(w). Multiplying out we have 3325=4w^2-45w. Move the constant over by subtraction and then we will have a quadratic that can be factored to solve for w. 4w^2-45w-3325=0. We would put that through the quadratic formula to solve for w. When we do that we get that w = 35 and w = -23.75. The 2 things in math that will never EVER be negative is time and distance/length, so -23.75 is out. That means that the width is 35. The length is 4(35) - 45 which is 95. The dimensions of your rectangle are length is 95 and width is 35. There you go!

8 0
3 years ago
Write the three numbers less then 40 that have 2 and 5 as factors
ozzi
No. which have factors 2 & 5 have 2 & 5 as their prime factor
therefore, No. are :
2*5 = 10
2*5*2 = 20
2*5*3 = 30
3 0
3 years ago
There are six bottles of juice for the same size and we need to make each kid have a 1/3 of a bottle how many kids will there be
solmaris [256]

Answer:

yes, 6÷1/3, which is 6×3 or 18

Step-by-step explanation:

4 0
3 years ago
You have 3/4 of a pound of peanuts. You have 10 cupcakes . What fraction of nuts is in each cupcake
kvasek [131]

Each cupcake would have 3/40 of a pound of nuts since that is 10x smaller than the total they have so they could put that amount into 10 cupcakes.

The answer is 3/40

8 0
3 years ago
Equations
sergij07 [2.7K]

Answer:

2x+12=24

first you subtract 12 from both sides

2x+12=24

-12. -12

The 12-12 should cancel itself, the rest of the equation you bring down to get

2x=12 (because 24-12=12)


Now you have 2x=12.
you then divide 2x by both sides.

2x=12

/2x=/2x

The 2x/2x cancels itself out so you then solve for 12/2x.

For this you just divide 12/2 which is 6!

x= 6 is your final answer.
to check this equation you can plug your number back into x to see if it is true! 2(6)+12=24.
6 times 2 is 12 and 12+12 is 24 so your answer (6) is true!


hope this helps! :D

4 0
2 years ago
Read 2 more answers
Other questions:
  • Which is the graph of the given function?
    11·1 answer
  • Help!! 10 PTS!!
    5·1 answer
  • The minute hand of a clock is 15 cm long how far does the tip of the minute and travel in 20 minutes
    8·1 answer
  • PLEASE HELP!!!
    12·1 answer
  • Reflect the point (-7, -9) across the x-axis: Then
    10·1 answer
  • Which number represents a square root of 3 (cosine (StartFraction pi Over 2 EndFraction) + I sine (StartFraction pi Over 2 EndFr
    5·1 answer
  • Which expression can be used to check the answer to 56 divided by (negative 14) = n?
    14·2 answers
  • Which triangle is a translation of the orange triangle?
    8·1 answer
  • What is the answer to this question?
    8·1 answer
  • Can yall help me out
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!