9) Let<br> X-2, x, x+3 <br> be the first 3 terms of a geometric sequence. FInd the value of x..

Sphere has a diameter of 14 ft. What is its surface area?

oksian1 [2.3K]

Good morning

A≈615.75ft²

have a great day

4 0

3 years ago

Two different types of polishing solutions are being evaluated for possible use in a tumble-polish operation for manufacturing i

Nina [5.8K]

Answer:

$z=\frac{0.843-0.653}{\sqrt{0.748(1-0.748)(\frac{1}{300}+\frac{1}{300})}}=5.358$

$p_v =2*P(Z>5.358) = 4.2x10^{-8}$

Comparing the p value with 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, and we can say that we have singificantly differences between the two proportions.

Step-by-step explanation:

Data given and notation

$X_{1}=253$ represent the number with no defects in sample 1

$X_{2}=196$ represent the number with no defects in sample 1

$n_{1}=300$ sample 1

$n_{2}=300$ sample 2

$p_{1}=\frac{253}{300}=0.843$ represent the proportion of number with no defects in sample 1

$p_{2}=\frac{196}{300}=0.653$ represent the proportion of number with no defects in sample 2

z would represent the statistic (variable of interest)

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

$\alpha=0.05$ significance level given

Concepts and formulas to use

We need to conduct a hypothesis in order to check if is there is a difference in the the two proportions, the system of hypothesis would be:

Null hypothesis: $p_{1} - p_2}=0$

Alternative hypothesis: $p_{1} - p_{2} \neq 0$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{253+196}{300+300}=0.748$

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.843-0.653}{\sqrt{0.748(1-0.748)(\frac{1}{300}+\frac{1}{300})}}=5.358$

Statistical decision

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

$p_v =2*P(Z>5.358) = 4.2x10^{-8}$

Comparing the p value with 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, and we can say that we have singificantly differences between the two proportions.

5 0

4 years ago

Rita paid for a $2.95 sandwich and a

Arlecino [84]

Lunch cost $4.14 and she got $5.86

4 0

2 years ago

A right triangle is ____ a scalene triangle.<br> Always, sometimes, or never

konstantin123 [22]

Answer: Sometimes

Step-by-step explanation:

This is a very tricky question. We know that in an isosceles triangle, two sides are the same. Because of this, we know that the right angle is always 90 degrees, and the other sides would be 45 degrees each because all triangles add up to 180 degrees. A right triangle could also be scalene, meaning none of the sides are the same, for example a scalene triangle could have sides of 44, 46, and 90 degrees. Rest assured, a right triangle will never be equalateral. Hope this helps :) Merry Christmas

4 0

3 years ago

Jacob has 96 books to stack on library shelves. Each shelf can hold 9 books. How many shelves will he need to stack all the book

weeeeeb [17]

Answer:

11 book shelves

Step-by-step explanation:

All you have to do is divide 69/9 =10.66

round up and get 11 book shelves

7 0

3 years ago

9) Let X-2, x, x+3 be the first 3 terms of a geometric sequence. FInd the value of x..