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2 years ago

14

How do you convert a fraction to a decimal? Say,

="\frac{2}{5}" alt="\frac{2}{5}" align="absmiddle" class="latex-formula"> ?

1 answer:

gladu [14]2 years ago

8 0

Answer:

you divide the top number by the bottom number

Step-by-step explanation:

2/5 = 0.4

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FLVS STUDENTS !!! For the 5.05 Two-Variable Linear Inequalities algebra 1 assignment can someone send me there answers ?!?!?!

iogann1982 [59]

Degree is the value of the highest power of the variable, and hence in this case is 8

6 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

If every dimension of a two-dimensional figure is multiplied by k, by what quantity is the area multiplied?

Igoryamba

For example: Square has dimension a
A = a² and if every dimension is multiplied by k new dimension would be:
A 1 = k² a² = k² A.
Or the area of rhombus: A = d1 * d 2 / 2
New area is: A 1 = k d 1 * k d 2 / 2 = k² A
Answer: If every dimension of two-dimensional figure is multiplied by k, the area is multiplied by k².

8 0

2 years ago

tamaranim1 [39]

Question 1: <span>The answer is D. which it ended up being <span>0.9979
</span>
Question 2: </span>The expression P(z > -0.87) represents the area under the standard normal curve above a given value of z. What is P(z > -0.87)? Express your answer as a decimal to the nearest ten thousand

The expression P(z > -0.87) represents the area under the standard normal curve above a given value of z. What is P(z > -0.87)? Express your answer as a decimal to the nearest ten thousandth (four decimal places). So being that rounding it off would mean your answer would be = ?

Question 3: <span>Assume that the test scores from a college admissions test are normally distributed, with a mean of 450 and a standard deviation of 100.
a. What percentage of the people taking the test score between 400 and 500?
b. Suppose someone receives a score of 630. What percentage of the people taking the test score better? What percentage score worse?
c. A university will not admit a student who does not score in the upper 25% of those taking the test regardless of other criteria. What score is necessary to be considered for admission? </span>z = 600-450 /100 = .5 NORMSDIST(0.5) = .691462<span><span> z = 400-450 /100 = -.5 NORMSDIST(-0.5) = .30854

P( -.5 < z <.5) = .691462 - .30854 = .3829 Or 38.29%
Receiving score of 630:
z = 630-450 /100 = 1.8 NORMSDIST(1.8) = .9641
96.41% score less and 3.59 % score better
upper 25%
z = NORMSINV(0.75)= .6745
.6745 *100 + 450 = 517 Would need score >517 to be considered for admissions </span><span>
Question 4: </span>The z-score for 45cm is found as follows:</span>
Reference to a normal distribution table, gives the cumulative probability as 0.0099.
<span>Therefore about 1% of newborn girls will be 45cm or shorter.</span>

6 0

3 years ago

Read 2 more answers

Do this only on number line

Tatiana [17]

#4

-2/8=-1/4
3/6=1/2

Refer to the attachment

#2

Mid point:-

-2/5+1/2/2
-4+5/10/2
1/10/2
1/20

4 0

1 year ago

Read 2 more answers