What is the value of x?

Write an expression that represents the volume of a rectangular prism (box) with length 2003-02-02-00-00_files/i0260000.jpg, wid

Flauer [41]

10cm 11cm 8cm 13xm 5cm

8 0

3 years ago

The time taken to prepare the envelopes to mail a weekly report to all executives in a company has a normal distribution, with a

telo118 [61]

Answer:

Mailing preparation takes 38.29 min max time to prepare the mails.

Step-by-step explanation:

Given:

Mean:35 min

standard deviation:2 min

and 95% confidence interval.

To Find:

In normal distribution mailing preparation time taken less than.

i.eP(t<x)=?

Solution:

Here t -time and x -required time

mean time 35 min

5 % will not have true mean value . with 95 % confidence.

Question is asked as ,preparation takes less than time means what is max time that preparation will take to prepare mails.

No mail take more time than that time .

by Z-score or by confidence interval is

Z=(X-mean)/standard deviation.

Z=1.96 at 95 % confidence interval.

1.96=(X-35)/2

3.92=(x-35)

X=38.29 min

or

Confidence interval =35±Z*standard deviation

=35±1.96*2

=35±3.92

=38.29 or 31.71 min

But we require the max time i.e 38.29 min

And by observation we can also conclude the max time from options as 38.29 min.

4 0

3 years ago

Three negative numbers are added together. Which of the following statements is correct about the sum?

sp2606 [1]

The sum will be negative

4 0

3 years ago

Weight gain during pregnancy. In 2004, the state of North Carolina released to the public a large data set containing informatio

pychu [463]

Answer:

1. B. H0: μ1−μ2=0, HA: μ1−μ2≠0

2. z=1.2114

3. P-value=0.2257

4. Do not reject H0

Step-by-step explanation:

We have to perfomr an hypothesis test to see if there is strong evidence that there is a significant difference between the two population means.

The null and alternative hypothesis are:

$H_0: \mu_1-\mu_2=0\\\\H_a: \mu_1-\mu_2\neq0$

Being μ1 the mean average gain for younger mothers and μ2 the mean average gain for mature mothers.

(NOTE: we are comparing means, not proportions, as it is the random variable is the weight gain).

As we are claiming "strong evidence", the level of significance will be 0.01.

For younger mothers, the sample size is n1=840, the sample mean is 30.7 and the sample standard deviation is s1=14.91.

For mature mothers, the sample size is n2=132, the sample mean is 29.15 and the sample standard deviation is s2=13.46.

The difference between means is

$M_d=\mu_1-\mu_2=30.7-29.15=1.55$

The standard error of the difference between means is

$s_M=\sqrt{\dfrac{s_1^2}{n_1}+\dfrac{s_2^2}{n_2}}=\sqrt{\dfrac{14.91^2}{840}+\dfrac{13.46^2}{132}}=\sqrt{ 0.2647+1.3725}=\sqrt{1.6372}\\\\\\s_M=1.2795$

Then, the statistic can be calculated as:

$z=\dfrac{M_d-(\mu_1-\mu_2)}{s_M}=\dfrac{1.55-0}{1.2795}=1.2114$

The P-value for this z-statistic in a two tailed test is:

$P-value=2P(z>1.2114)=0.2257$

As the P-value is greater than the significance level, the null hypothesis failed to be rejected.

There is no enough evidence to claim that the real average weight gain differs from mature and youger mothers.

5 0

3 years ago

Why is a sequence a function and how can you write a rule for a sequence?

statuscvo [17]

Certain sequences (not all) can be defined (expressed) in a "recursive" form. 
In a recursive formula, each term is defined as a function of its preceding term(s). 
[Each term is found by doing something to the term(s) immediately in front of that term.] 
A recursive formula designates the starting term, a1, and the nth term of the sequence, an , as an expression containing the previous term (the term before it), an-1.

The process of recursion can be thought of as climbing a ladder.
To get to the third rung, you must step on the second rung. Each rung on the ladder depends upon stepping on the rung below it.You start on the first rung of the ladder. a1
From the first rung, you move to the second rung. a2
 a2 = a1 + "step up"
From the second rung, you move to the third rung. a3
 a3 = a2 + "step up"
If you are on the nth rung, you must have stepped on the n-1st rung. an = an-1 + "step up"Notation: Recursive forms work with the term(s) immediately in front of the term being examined. The table at the right shows that there are many options as to how this relationship may be expressed in notations.A recursive formula is written with two parts: a statement of the first term along with a statement of the formula relating successive terms.The statements below are all naming the same sequence:Given TermTerm in front
of Given Terma4a3anan-1an+1anan+4an+3f (6)f (5)f (n)f (n-1)f (n+1)f (n)

 Sequence: {10, 15, 20, 25, 30, 35, ...}. Find a recursive formula.
This example is an arithmetic sequence (the same number, 5, is added to each term to get to the next term).

7 0

3 years ago