All categories

3 years ago

How do a parameter and a statistic differ? Choose the correct answer below.

Mathematics

1 answer:

gayaneshka [121]3 years ago

5 0

Answer:

Step-by-step explanation:

A parameter is a summary measure computed to describe a characteristic of the population and it involves the measurement of all in the population numerically/quantitatively. e.g Average of all the values measured in the population

A statistic is a measurement based on sample observations.

Examples of statistics constructed from a random sample : [ $X_{1}.....X_{n}$

(a) max $(x_{1}....x_){n}$

(b) Average of the observed values

You might be interested in

A Survey of 85 company employees shows that the mean length of the Christmas vacation was 4.5 days, with a standard deviation of

GenaCL600 [577]

Answer:

The 95% confidence interval for the population's mean length of vacation, in days, is (4.24, 4.76).

The 92% confidence interval for the population's mean length of vacation, in days, is (4.27, 4.73).

Step-by-step explanation:

We have the standard deviations for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 85 - 1 = 84

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 84 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.95}{2} = 0.975$ . So we have T = 1.989.

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 1.989\frac{1.2}{\sqrt{85}} = 0.26$

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 4.5 - 0.26 = 4.24 days

The upper end of the interval is the sample mean added to M. So it is 4.5 + 0.26 = 4.76 days

The 95% confidence interval for the population's mean length of vacation, in days, is (4.24, 4.76).

92% confidence interval:

Following the sample logic, the critical value is 1.772. So

$M = T\frac{s}{\sqrt{n}} = 1.772\frac{1.2}{\sqrt{85}} = 0.23$

The lower end of the interval is the sample mean subtracted by M. So it is 4.5 - 0.23 = 4.27 days

The upper end of the interval is the sample mean added to M. So it is 4.5 + 0.23 = 4.73 days

The 92% confidence interval for the population's mean length of vacation, in days, is (4.27, 4.73).

8 0

3 years ago

PLEASE HELP!!! Would you rather paint 3/4 of a circle or a circular ring? Using area, explain your reasoning. Include calculatio

Nostrana [21]

Answer: I would paint either of the 3/4 of a circle or a circular ring.

Step-by-step explanation: We shall start by calling the three quarter circle on the left A, and the ring on the right we shall call B.

The area of both can be calculated and that figure which results in the lesser value (of area) shall cost you less to paint.

For A, the area of the circle is given as

Area = πr²

Where π shall be taken as 3.14 and the radius r is 6.

Area = 3.14 * 6²

Area = 3.14 * 36

Area = 113.04

The area of the quarter of the circle would be subtracted from the total area as shown in the calculation above.

Area of sector = ∅/360 * πr²

The sector is a quarter of the circle and that makes the angle at the sector to be equal to (360/4) 90 degrees. Therefore ∅ equals 90.

Area of sector = (90/360) * 113.04

Area of sector = 1/4 * 113.04

Area of sector = 28.26

Area of A therefore is derived as;

Area of A = 113.04 - 28.26

Area of A = 84.78 square metres

For B, the area of the ring is given as follows;

Area of B = Area of larger circle - Area of smaller circle

Area of B = πR² - πr²

Where R is the radius of the larger circle and r is the radius of the smaller inner circle. By factorizing the right hand side of the equation, we now have;

Area of B = π (R² - r²)

Area of B = 3.14 (6² - 3²)

Area of B = 3.14 (36 - 9)

Area of B = 3.14 * 27

Area of B = 84.78 square metres.

From the calculations shown along with the explanations, both the three-quarters and the ring have exactly the same area, which means you are going to spend exactly the same quantity of paint and spend the same amount of time painting either one of them.

So the answer is; I would paint EITHER ONE OF THEM.

3 0

3 years ago

Courtney has 12 fewer stickers than tina. how many stickers does courtney have in terms of x?

Annette [7]

Answer:

X-12

X×4

X + 7

X x 2/3

Step-by-step explanation:

6 0