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
inysia [295]
3 years ago
9

A local weather enthusiast wants to see if the last five summers have been warmer than normal for Eloy, Arizona. From the Nation

al Oceanic and Atmospheric Administration (NOAA), he knows the 30-year average for July was 90° with a standard deviation of 2.1°. The last five summers recorded have an average of 93.5°. If he uses a = 5%, which of the following would be valid based on the data he has gathered?
Mathematics
2 answers:
lys-0071 [83]3 years ago
5 0

Answer:


Step-by-step explanation:

This is a question on hypothesis testing.

Population mean based on 30 year average for July was 90 with

a std deviation of 2.1

Sample of 5 shows average 93.5

To check whether sample average = population average

H0: x bar =90

Ha: x bar not equal 90(Two tailed test)

Test statistic = \frac{93.5-90}{\frac{2.1}{\sqrt{5} } }

=3.73

Since this lies outside the range (-1.96, 1.96) we reject null hypothesis

Hence we cannot say sample mean equals 90

Viefleur [7K]3 years ago
3 0

Answer:

D

Step-by-step explanation:

You might be interested in
A fashion designer wants to know how many new dresses women buy each year. Assume a previous study found the standard deviation
horsena [70]

Answer:

649

Step-by-step explanation:

Given that

Mean number of dresses is 5.5

Standard deviation of the sample, S.D is 1.3

Margin of error, M.E is 0.1

Level of confidence is 95% or 0.95

The formula for margin of error, M.E is

Z * (S.D/√n) , where

Z = Value for level of confidence which is 1.96

Proceeding further, we have

0.1 = 1.96 * (1.3/√n)

0.1 = 2.548 / √n, making √n subject of formula, we have

√n = 2.548 / 0.1

√n = 25.48, squaring both sides

n = 25.48²

n = 649.23

Therefore the number of sample size we're looking for is n = 649.23, when rounded to the nearest integer, we have it to be 649

4 0
3 years ago
Ella went trick-or-treating with her family. When
Kazeer [188]

Answer:

Step-by-step explanation:

5 0
2 years ago
Read 2 more answers
Find the solution of the system of equations shown on the graph.
eduard

Answer:

<h2>(0, 3) → x = 0, y = 3</h2>

Step-by-step explanation:

The solution to the system of equations is the intersection of lines.

Look at the picture.

6 0
3 years ago
The lines shown below are parallel. If the green line has a slope of -3/7, what is
trapecia [35]

Answer:

-3/7

Step-by-step explanation:

Parallel lines have the same slope

If the green line has a slope of -3/7, the red line has a slope of -3/7

8 0
3 years ago
Please help me! I will make you the Brainliest!
BARSIC [14]

Answer: Is it C

Step-by-step explanation:

7 0
2 years ago
Other questions:
  • King kyle orders the construction of his future mausoleum ( a fancy tomb) so that people never forget his awesomeness. His archi
    12·2 answers
  • Which answer is a reasonable estimate to the following problem 94-689 60,000. 70,000. 600,000 700,000
    8·1 answer
  • A car is driving at a speed of 40 mi/h. What is the speed of the car in feet per minute? a. 2,400 ft/min b. 211,200 ft/min c. 3,
    15·1 answer
  • The number7 less than z is_______
    7·1 answer
  • Through: (4,4), slope<br> 9/4
    7·1 answer
  • Terry has 3 pairs of pants (black, khaki, and brown) and 4 shirts (yellow, red, blue, and white). He does not care which colors
    7·1 answer
  • A recipe requires 1/2 cup of milk for each 1/4 cup of water. How many cups of water are needed for each
    7·1 answer
  • 30. What is the degree of the polynomial?
    10·1 answer
  • The value of cos47° is equal to​
    15·1 answer
  • Pleasseeeee help !!!!
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!