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3 years ago

What is the mean of the set of numbers? {–8, –4, –3, –11}

1 answer:

7 0

The answer is A. The mean is the average of the numbers. It is easy to calculate: add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count. -8+-4+-3+-11=-26 -26÷4=-6.5

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A. If a bus travels 6km in to minutes, what<br>distance does it travel in Isecondo

mina [271]

Answer:

60 second

Step-by-step explanation:

6km into minutes

1 minutes is 60 second

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3 years ago

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The manager of a fleet of automobiles is testing two brands of radial tires and assigns one tire of each brand at random to the

Darya [45]

Answer:

Brand 1 Brand 2 Difference

37734 35202 2532

45299 41635 3664

36240 35500 740

32100 31950 150

37210 38015 −805

48360 47800 560

38200 37810 390

33500 33215 285

Sum of difference = 2532+ 3664+740+150 −805+ 560 +390 +285 = 7516

Mean = $d=\frac{7516}{8}$

Mean = $d=939.5$

a) d= 939.5

$\text{Sample Standard deviation, s} = \sqrt{\dfrac{(x-\bar{x})^2}{n-1}}$

$=\sqrt{\dfrac{(2532-939.5)^2+(3664-939.5)^2+(740-939.5)^2 ...+(285-939.5)^2}{8-1}}$

=1441.21

b)SD= 1441.21

c)Calculate a 99% two-sided confidence interval on the difference in mean life.

confidence level =99%

significance level =α= 0.01

Degree of freedom = n-1 = 8-1 =7

So, $t_{\frac{\alpha}{2}}=3.499$

Formula for confidence interval $= \left( \bar{X} \pm t_{\frac{\alpha}{2}} \times \frac{s}{\sqrt{n}} \right)$

Substitute the values

confidence interval $= 939.5 \pm 3.499 \times \frac{1441.21}{\sqrt{8}} \right)$

confidence interval $= 939.5 - 3.499 \times \frac{1441.21}{\sqrt{8}} \right)$ to $= 939.5 + 3.499 \times \frac{1441.21}{\sqrt{8}} \right)$

Confidence interval $−843.396\$ to $2722.396$

8 0

3 years ago

The figure below shows a shaded rectangular region inside a large rectangle:

Westkost [7]

The answer to your question is 64.

7 0

3 years ago

The vertices of a triangle are A(1, –9), B(0, –3), C(–4, –5). Fine the length of each side. What type of triangle is triangle AB

Alenkinab [10]

Answer:

AB = √37

BC = 2√5

AC = √41

Type: SCALENE TRIANGLE

Step-by-step explanation:

Given the coordinates

A(1, –9), B(0, –3), C(–4, –5)

We are to find the length of each sides first. Using the formula for calculating the distance between two points, we will have;

For A(1, –9) and B(0, –3)

AB = √(-3+9)²+(0-1)²

AB = √6²+(-1)²

AB = √36+1

AB = √37

For coordinates B(0, –3) and C(–4, –5)

BC = √(-5+3)²+(-4-0)²

BC= √(-2)²+(-4)²

BC = √4+16

BC = √20

BC = 2√5

For coordinates A(1, –9), C(–4, –5)

AC = √(-5+9)²+(-4-1)²

AC= √(4)²+(-5)²

AC = √16+25

AC = √41

<em>Since the sides of the triangles are all different, hence the triangle is a SCALENE triangle</em>

8 0

3 years ago

In a metal fabrication process, metal rods are produced to a specified target length of 15 feet. Suppose that the lengths are n

Leto [7]

Answer:

95% Confidence interval: (14.4537 ,15.1463)

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 15 feet

Sample mean, $\bar{x}$ = 14.8 feet

Sample size, n = 16

Alpha, α = 0.05

Sample standard deviation, σ = 0.65 feet

Degree of freedom = n - 1 = 15

95% Confidence interval:

$\bar{x} \pm t_{critical}\displaystyle\frac{s}{\sqrt{n}}$

Putting the values, we get,

$t_{critical}\text{ at degree of freedom 15 and}~\alpha_{0.05} = \pm 2.1314$

$14.8 \pm 2.1314(\dfrac{0.65}{\sqrt{16}} ) \\\\= 14.8 \pm 0.3463 = (14.4537 ,15.1463)$

is the required confidence interval for the true mean length of rods.

3 0

3 years ago

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