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
tensa zangetsu [6.8K]
3 years ago
12

A friend of yours is not taking statistics, wonders why it is that anyone would choose to take a sample. "Obviously," she says,

"you would get better information from a census." In a short paragraph, explain why it is that statisticians take samples rather than taking a cenus.
Mathematics
1 answer:
olga nikolaevna [1]3 years ago
6 0
A census is where you poll everybody; a sample is where you choose a group of people to poll. Taking a census is inefficient because you can get almost completely accurate information from a large sample, but a sample would take significantly less time than a census since you wouldn't have to poll absolutely everybody in a population.
You might be interested in
Lightbulbs of a certain type are advertised as having an average lifetime of 750 hours. The price of these bulbs is very favorab
Katyanochek1 [597]

Answer:

(a) Customer will not purchase the light bulbs at significance level of 0.05

(b) Customer will purchase the light bulbs at significance level of 0.01 .

Step-by-step explanation:

We are given that Light bulbs of a certain type are advertised as having an average lifetime of 750 hours. A random sample of 50 bulbs was selected,  and the following information obtained:

Average lifetime = 738.44 hours and a standard deviation of lifetimes = 38.2 hours.

Let Null hypothesis, H_0 : \mu = 750 {means that the true average lifetime is same as what is advertised}

Alternate Hypothesis, H_1 : \mu < 750 {means that the true average lifetime is smaller than what is advertised}

Now, the test statistics is given by;

       T.S. = \frac{Xbar-\mu}{\frac{s}{\sqrt{n} } } ~ t_n_-_1

where, X bar = sample mean = 738.44 hours

               s  = sample standard deviation = 38.2 hours

               n = sample size = 50

So, test statistics = \frac{738.44-750}{\frac{38.2}{\sqrt{50} } } ~ t_4_9

                            = -2.14

(a) Now, at 5% significance level, t table gives critical value of -1.6768 at 49 degree of freedom. Since our test statistics is less than the critical value of t, so which means our test statistics will lie in the rejection region and we have sufficient evidence to reject null hypothesis.

Therefore, we conclude that the true average lifetime is smaller than what is advertised and so consumer will not purchase the light bulbs.

(b) Now, at 1% significance level, t table gives critical value of -2.405 at 49 degree of freedom. Since our test statistics is higher than the critical value of t, so which means our test statistics will not lie in the rejection region and we have insufficient evidence to reject null hypothesis.

Therefore, we conclude that the true average lifetime is same as what it has been advertised and so consumer will purchase the light bulbs.

6 0
3 years ago
Estimint 697 times 3
frutty [35]
700 times 3 is 2,100, You get 700 from estimating 697
4 0
3 years ago
The function y = f (x) is graphed below. What is the average rate of change of the function f(x) on the interval - 1 ≤ x ≤ 3?
jonny [76]

Answer:

\displaystyle -2

General Formulas and Concepts:

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right

<u>Algebra I</u>

  • Average Rate of Change: \displaystyle \frac{f(b) - f(a)}{b - a}

Step-by-step explanation:

<u>Step 1: Define</u>

Interval -1 ≤ x ≤ 3

a = -1, b = 3

f(a) = f(-1) = 4

f(b) = f(3) = -4

<u>Step 2: Find Average</u>

  1. Substitute in variables [ARC]:                     \displaystyle \frac{f(3) - f(-1)}{3 + 1}
  2. Substitute:                                                   \displaystyle \frac{-4 - 4}{3 + 1}
  3. [Fraction] Subtract/Add:                             \displaystyle \frac{-8}{4}
  4. [Fraction] Divide:                                        \displaystyle -2
4 0
2 years ago
-3(n+9)=15<br> i need the step of solving this plzz brainliest if right!!
raketka [301]

Answer:

n = -14

Step-by-step explanation:

-3(n+9)=15

Distribute -3 to (n+9):

-3n - 27 = 15

Add 27 to both sides:

-3n = 42

Divide both sides by -3:

n = -14

5 0
2 years ago
Please answer my questions!
timama [110]

Answer:

What is the question.

Step-by-step explanation:

Cant help u without one.

4 0
3 years ago
Other questions:
  • 2. Alicia is writing the program for a video game. For one part of the game she uses the rule to move points on the screen.
    10·1 answer
  • How to find the degree of each monomial?
    12·1 answer
  • Jan mixed 2 pints of blue paint with 5 pints of red paint to make purple paint. He wrote the equation b= ( )r to represent the p
    5·1 answer
  • How do you simplify x^2-4x-21 divided by x+3
    7·1 answer
  • What is 35 percent of 40 as a fraction?
    11·2 answers
  • Im on a time limit please help i will give brainliest!
    14·1 answer
  • Is the answer I wrote correct?
    13·1 answer
  • A poll reported 42% of voters favor the Republican candidate in an upcoming election. Assume that this percentage is true for th
    7·1 answer
  • Find the volume and round to the nearest whole number
    9·1 answer
  • If f(x)=5x^2-3x-1f(x)=5x 2 −3x−1, then what is the remainder when f(x)f(x) is divided by x+10x+10?
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!