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Answer:

Step-by-step explanation:

Here are the missing values;

Mean μ = 15.5 minutes

Standard deviation = 1.7 minutes

A Random sample of 90 completion

The sample mean = 15.4 minutes

Level of significance = 0.1

Then the following analysis can be made on the above study.

Firstly, the null hypothesis is [tex]\mathbf{H_o : \mu = 15.5}[/tex]

the alternative hypothesis is [tex]\mathbf{H_a: \mu < 15.5}[/tex]  

Since, the value is less than, then this is a one-tailed test.

The Z test statistics can be computed as:

[tex]Z = \dfrac{ \overline x - \mu }{\dfrac{\sigma}{\sqrt{n}} } \ \ \sim \ \ N(0.1)[/tex]

[tex]Z = \dfrac{ 15.4-15.5 }{\dfrac{1.7}{\sqrt{90}} }[/tex]

[tex]Z = \dfrac{ -0.1 }{\dfrac{1.7}{ 9.4868} }[/tex]

Z = −0.560

The critical value of Z at 0.1  level  of significance is:

[tex]Z_{0.1} = -1.28[/tex]

Decision Rule: We fail to reject the null hypothesis sInce -0.560 > -1.28

Conclusion: NO, there is no evidence to support the claim that the mean completion time has decreased. We conclude that the mean completion time remains at 15.5 minutes.

Answer:

CI  = ( 36,6  ;  41,4 )

Step-by-step explanation:

CI = 99,9  %       α = 0,1 %      α = 0,001

We find z scre for α = 0,001 in z -table

z(s) = - 3,08

CI =  μ₀  ±  MOE          where    μ₀  = 39 min  and   MOE = z(s) * σ/√n

CI = 39  ±   3,08 * 4,8 / √37

CI = 39  ±   2,4315

CI  = ( 36,6  ;  41,4 )

Answer:

Step-by-step explanation:

If the wall is perpendicular, then that means that this is a right triangle. We can find out if it is by using Pythagorean's Theorem and filling in the values for the sides. If the statement is true, then the triangle is right and the wall is perpendicular to the base.

[tex]a^2+b^2=c^2[/tex] and filling in:

[tex]7^2+8^2=12^2[/tex] Let's find out if this is true:

[tex]49+64=144[/tex] Is this true?

113 = 144

Definitely not true. So this is not a right triangle and the wall is not perpendicular to the floor.

Answer:

σ = 0,11

Step-by-step explanation:

We assume the boxes filling process follows a Normal Distribution, then

z(score) = ( X - μ ) /σ     or   z(score) = ( μ - X ) /σ  

depending of the tail of the curve ( as we are evaluating boxes below mean we need to use the second equation )

where   μ  and σ are the mean and the standard deviation of the population

As the goal is to have boxes with no higher than 16,2 ou and only  4% of underweight boxes

4%   is 0,04   that should be the area under the bell shape curve then from z table we find z(s)

z(s) = - 1,75

z(s)  = ( μ - X )/σ

- 1,75 = ( 16,2 - 16 ) / σ

σ = 0,2 / 1,75

σ = 0,11

Answer:

0.79 ; 0.753

Step-by-step explanation:

Given that:

Students who have spent at least five hours studying GMAT review guides have a probability of 0.85 of scoring above 400 :

≥ 5 hours review = 0.85

Students who do not spend at least five hours reviewing have a probability of 0.65 of scoring above 400

< 5 hours = 0.65

70% (0.7) of business students spend atleast 5 hours review time

A.) probability of scoring above 400

(Proportion who spend atleast 5 hours review time * 0.85) + (Proportion who do not spend atleast 5 hours * 0.65)

Proportion who do not spend atleast 5 hours = (1 - proportion who spend atleast 5 hours) = 1 - 0.7 = 0.3

Hence,

P(scoring above 400) = (0.7 * 0.85) + (0.3 * 0.65) = 0.595 + 0.195

= 0.79

B.) probability that given a student scored above 400, he/she spent at least five hours reviewing for the test.

P(spent ≥5 hours review | score above 400) :

P(spent ≥5 hours review) / P(score > 400)

(0.7 * 0.85) / 0.79

0.595 / 0.79

= 0.753

Answer:

P [ X > 23,22 ]  = 0,8798      or  P [ X > 23,22 ]  =  87,98 %

Step-by-step explanation:

P [ X > 23,22 ]  =  1  -  P [X ≤ 23,22 ]

P [X ≤ 23,22 ] =  ( X - μ₀ ) / σ /√n

P [X ≤ 23,22 ] = ( 23,22 - 36,25 )/ 6,50/√36

P [X ≤ 23,22 ] =  - 13,03 *6 / 6,50

P [X ≤ 23,22 ] = - 12,02        or       P [X ≤ 23,22 ] = 12,02 %

(note the - sign only mean that values on the left tail of the bell shape curve)

Then

P [ X > 23,22 ]  =  1  -  0,1202

P [ X > 23,22 ]  = 0,8798      or  P [ X > 23,22 ]  =  87,98 %

Answer:

0

Step-by-step explanation:

Answer:

x = 3b/2 + 3y/2

Step-by-step explanation:

Goal: Find x

To do that we must isolate x on one side of the equation.

2/3x - y = b

2/3x - y + y = b + y

2/3x = b + y

2/3x ÷ 2/3 = b + y ÷ 2/3

(When we divide fractions we multiply by its reciprocol.)

x = 3b/2 + 3y/2

I hope this helped and if it did I would appreciate it if you marked me Brainliest. Thank you and have a nice day!

Answer:

[tex]1 \div 6 \times 72 = 12[/tex]

Answer:

Answer is 75cm squared.

Step-by-step explanation:

10x15 = 150

divide by 2

final answer is 75.

Answer:

600

Step-by-step explanation:

Answer:

52% play video games on their personal computer.

Step-by-step explanation:

884/1700 = 52%

Answer:

y=55 when x is 33

Step-by-step explanation:

Use the direct variation formula:

[tex]\frac{y}{x} =k[/tex]  or [tex]\frac{y}{x} =\frac{y}{x}[/tex]

Insert the given values:

[tex]\frac{15}{9}=\frac{y}{33}[/tex]

To simplify the equation, cross multiply:

[tex]15(33)=9(y)\\\\495=9y[/tex]

Isolate the variable. Divide both sides by 9:

[tex]\frac{495}{9} =\frac{9y}{9} \\\\55=y[/tex]

Therefore, when x is 33, y is 55.

:Done

Answer:

A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable. This increases the reliability of the results, often through a comparison between control measurements and the other measurements.

Answer:

The greatest number is 11

Step-by-step explanation:

Given

Dividends: 181 and 236

Remainder: 5

Required

Determine a divisor that satisfies the above condition

Let the required divisor be represented with x.

Since a remainder of 5 is expected, then x can divide (181 - 5) and (236 - 5) without remainders.

So, we have:

[tex]181 - 5 = 176[/tex]

[tex]236 - 5 = 231[/tex]

Next, we calculate the GCF of 176 and 231

[tex]176 = 2 * 2 * 2 * 2 * 11[/tex]

[tex]231 = 3 * 7 * 11[/tex]

The greatest common factor, GCT is:

[tex]GCF = 11[/tex]

Hence, the required divisor is 11

Answer:

option A = 40(24) = option B = x (.1) where x is her gross sales

40(24) = x(.1)

40(24)/.1 = x = sales = $9600

Hope this helps....

Answer:1,920

Step-by-step explanation: First find the 24$ wage. which would be 960$. then you divide that by .5 which would equal

1920

first we do

square is length 6 so base =6

10-6=4

the rectangle is 2 by 4

base=4

square is 6 by 6

rectangle is 4 by 2

split the triangles up

area of triangle=1/2base times height

rectangle triangle base=4

height=2, area=1/2 times 2 times 4=4

square triangle

flip 90 degrees clockwise so we have base=2

height=6

area=1/2 times 2 times 6=6

add

4+6=10

total area=10m^2

Answer:

I think it's E, F, H

Step-by-step explanation:

Hope you got it.

Merry Christmas...

Answer:

90

Step-by-step explanation:

90

Answer:- Things look 250 larger.

Answer:

2,500x.

Step-by-step explanation:

Answer:

WY = 30

XZ = 10.5

Step-by-step explanation:

Paralellogram's diagonal's bisect eachother

Therefore,

[tex]n + 7 = 3 n[/tex]

Move the n over,

2n = 7

Divide both sides by 2,

n = 3.5

WY = 2(ZY) because definition of bisector

Simplify...

WY = 2(4n+1)

WY = 2(4(3.5)+1)

WY = 2(15)

WY = 30

You asked for XY, but the question asks for XZ, so I'm going to give XZ.

With n = 3.5 from above,

XZ = 3n

XZ = 3(3.5)

XZ = 10.5

The measure of XY and WY are; WY = 30 and XZ = 10.5

That quadrilateral in which opposite sides are parallel is called a parallelogram.

Thus, a parallelogram is always a quadrilateral but a quadrilateral can or cannot be a parallelogram.

Since Paralellogram's diagonal's bisect each other

Therefore,

2n = 7

Divide both sides by 2;

n = 3.5

WY = 2(ZY)

because definition of bisector

Simplify;

WY = 2(4n+1)

WY = 2(4(3.5)+1)

WY = 2(15)

WY = 30

we asked for XY,

With n = 3.5 from above,

XZ = 3n

XZ = 3(3.5)

XZ = 10.5

The measure of XY and WY are; WY = 30 and XZ = 10.5

Learn more about parallelogram;

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Answer:

Descriptive Statistics is used to   collect, organize and  summarize sample data.

Step-by-step explanation:

Descriptive Statistics is used to   collect, organize and  summarize sample data.

First of all he will collect a sample or maybe samples. A sample is a subset of the data drawn from the population. Here it will be the number of children from different households.

Populations can be described by parameters . These parameters can be inferred on the sample parameters. For example the population mean ,  population variance can be estimated by sample mean and sample mean.

These variables can be further categorized as discrete.

Now he will apply various test to check whether the inferences drawn about the population are true or not.

Answer:

yes because it says it only has red balls it didn't say any other color or something

Answer: The answer is m=300.

Step-by-step explanation: Step 1. Simplify the both sides of the equation:

[tex]\frac{-1}{15}m=-20[/tex].

And step 2. Multiply the both sides by [tex]\frac{15}{(-1)}:[/tex]

[tex](\frac{15}{-1})*(\frac{-1}{15}m)=(\frac{15}{-1})*(-20).[/tex] I hoped this is very helpful, please mark me as brainliest, and happy new year!! :D

Solving for the value of m in the given equation, m / -15 = -20, will give us: m = 300.

To solve for a variable in an equation, isolate the variable on one side of the equation by performing inverse operations (such as addition, subtraction, multiplication, or division) to both sides until the variable is left alone.

To solve for m in the equation m/-15 = -20, we can isolate m by multiplying both sides of the equation by -15 (the reciprocal of -1/15). This will cancel out the denominator on the left side and give us the value of m.

Step 1: Multiply both sides of the equation by -15:

(-15) * (m/-15) = (-15) * (-20)

Step 2: Simplify:

m = 300

Therefore, the value of m is 300.

Learn more about equation on:

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Answer:

Z score with a confidence level of 95% is 1.96

Step-by-step explanation:

The computation of the z score with the confidence level of 95% is shown below:

While determining the margin of error for the normally distributed population from the sample, the z score of the confidence level of 95% is 1.96

The same is to be considered

Therefore the third option is correct

Answer:

0.425

Step-by-step explanation:

40x2.5=100

17x2.5=42.5

So the fraction is 42.5/100 which is 0.425

Answer:

0.865

Step-by-step explanation:

Given that:

Disease is found in 1 out of 12000 people ; probability that disease is found in atleast one out of 24000 people

Using the binomial probability formula :

P(x = x) = nCx * p^x * (1 - p)^(n-x)

p = 1/ 12000 = 0.0000833333

n = 24000

P(x ≥ 1) = p(x = 1) + p(x =2) + ... + p(x = 24000)

In other to save computation time, we can employ the use of an online binomial probability calculator or a Ti-89 calculator :

The result is thus : 0.86467588659

P(x ≥ 1) = 0.865

Answer:

Step-by-step explanation:

17