How to draw the construction lines?

A farmer ordered 3/4 ton of soil. He wants to divide it evenly into 8 flower beds. How much will he have for each bed?

nasty-shy [4]

We know that
Total soil--------> 3/4 ton
divide it by 8
(3/4)/8----> 3/(4*8)----> 3/32 ton----> 0.09375 ton----> multiply by 1000---> 93.75 kg

the answer is
93.75 kg for each bed

7 0

3 years ago

The national mean annual salary for a school administrator is $90,00 a year (The Cincinnati Enquirer, April 7, 2012). A school o

timurjin [86]

Answer:

a) Null hypothesis: $\mu = 90000$

Alternative hypothesis: $\mu \neq 90000$

b) $p_v =2*P(t_{(24)}$

c) If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean for the salary differs from 9000 at 5% of significance.

Step-by-step explanation:

1) Data given and notation

77600 ,76000 ,90700 ,97200 ,90700 ,101800 ,78700 ,81300 ,84200 ,97600 ,

77500 ,75700 ,89400 ,84300 ,78700 ,84600 ,87700 ,103400 ,83800 ,101300

94700 ,69200 ,95400 ,61500 ,68800

We can calculate the sample mean and deviation with the following formulas:

$\bar X =\frac{\sum_{i=1}^n X_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

The values obtained are:

$\bar X=85272$ represent the mean annual salary for the sample

$s=11039.23$ represent the sample standard deviation for the sample

$n=25$ sample size

$\mu_o =90000$ represent the value that we want to test

$\alpha=0.05$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

Part a: State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean salary differs from 90000, the system of hypothesis would be:

Null hypothesis: $\mu = 90000$

Alternative hypothesis: $\mu \neq 90000$

If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Part b: Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{85272-90000}{\frac{11039.23}{\sqrt{25}}}=-2.141$

P-value

The first step is calculate the degrees of freedom, on this case:

$df=n-1=25-1=24$

Since is a two sided test the p value would be:

$p_v =2*P(t_{(24)}$

Part c: Conclusion

If we compare the p value and the significance level given $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean for the salary differs from 9000 at 5% of significance.

6 0

3 years ago

Please help me this is due in less than 45 minutes!

Natasha_Volkova [10]

Answer:

1.) It's 20th century painting

2.) 0.5 probability

Step-by-step explanation:

If the universal = 60

We need to first get the value of X. That is,

x (x - 2) + x + 2x + 8 + 10 = 60

First open the bracket

x^2 - 2x + x + 2x + 8 + 10 = 60

x^2 + x + 18 = 60

x^2 + x - 42 = 0

Factorise the above equation

x^2 + 7x - 6x - 42 = 0

x (x + 7) -6(x + 7) = 0

x = 6 or - 7

Since x can't be negative, so we will ignore -7

The value for T = 6(6 - 2) = 6×4 = 24

The value for B = 2(6) + 8 = 12 + 8 = 20

If a painting is chosen from random,

If it's from 20th century, the probability will be 34/60 = 0.567

If it's from British painting, the probability will be 30/60 = 0.5

We can therefore conclude that it's from 20th century painting since it has higher value of probability.

The the probability of choosing a British painting will be 30/60 = 0.5

5 0

3 years ago

50 points! Look at the picture attached. I will mark brainliest

Radda [10]

I’m pretty sure the answer would be 116

8 0

3 years ago

Read 2 more answers

Which points lie on the line whose equation is 8x - 2y + 7 = -9? Select all that apply.

Anestetic [448]

Answer:

A.(-2, 0)

C. (-1.4)

Step-by-step explanation:

we know that

If a point lie on the line, then the point must satisfy the equation of the line (makes the equation true)

we have

$8x-2y+7=-9$

subtract 7 both sides

$8x-2y=-9-7$

$8x-2y=-16$

divide by 2 both sides

$4x-y=-8$

Substitute the value of x and the value of y of each point in the linear equation and analyze the result

Verify each point

case A) we have

(-2, 0)

For x=-2, y=0

substitute

$4(-2)-(0)=-8$

$-8=-8$ ---> is true

so

the point lie on the line

case B) we have

(1, 3)

For x=1, y=3

substitute

$4(1)-(3)=-8$

$1=-8$ ---> is not true

so

the point not lie on the line

case C) we have

(-1, 4)

For x=-1, y=4

substitute

$4(-1)-(4)=-8$

$-8=-8$ ---> is true

so

the point lie on the line

case D) we have

(1, -4)

For x=1, y=-4

substitute

$4(1)-(-4)=-8$

$8=-8$ ---> is not true

so

the point not lie on the line

case E) we have

(0, -1)

For x=0, y=-1

substitute

$4(0)-(-1)=-8$

$1=-8$ ---> is not true

so

the point not lie on the line

7 0

3 years ago