The length of each side of a square was increased by 6 inches, so the

Researchers studying starfish collected two independent random samples of 40 starfish. One sample came from an ocean area in the

krek1111 [17]

Answer:

The test statistic for the appropriate test is $\frac{0.15-0.275}{\sqrt{0.2125(1-0.2125)[\frac{1}{40}+\frac{1}{40}]}}$ .

Step-by-step explanation:

The experiment conducted here is to determine whether there is a difference in proportion of starfish over 8 inches in length in the two ocean areas, i.e. north and south.

The hypothesis to test this can be defined as follows:

H₀: There is no difference in proportion of starfish over 8 inches in length in the two ocean areas, i.e. p₁ = p₂.

Hₐ: There is a difference in proportion of starfish over 8 inches in length in the two ocean areas, i.e. p₁ ≠ p₂.

The two-proportion z-test would be used to perform the test.

A sample of n = 40 starfishes are selected from both the ocean areas.

It provided that of the 40 starfish from the north, 6 were found to be over 8 inches in length and of the 40 starfish from the south, 11 were found to be over 8 inches in length.

Compute the sample proportion of starfish from north that were over 8 inches in length as follows:

$\hat p_{n}=\frac{6}{40}=0.15$

Compute the sample proportion of starfish from south that were over 8 inches in length as follows:

$\hat p_{s}=\frac{11}{40}=0.275$

The test statistic is:

$z=\frac{\hat p_{n}-\hat p_{s}}{\sqrt{P(1-P)[\frac{1}{n_{n}}+\frac{1}{n_{s}}]}}$

Compute the combined proportion P as follows:

$P=\frac{X_{n}+X_{s}}{n_{n}+n_{s}}=\frac{6+11}{40+40}=0.2125$

Compute the test statistic value as follows:

$z=\frac{\hat p_{n}-\hat p_{s}}{\sqrt{P(1-P)[\frac{1}{n_{n}}+\frac{1}{n_{s}}]}}$

$=\frac{0.15-0.275}{\sqrt{0.2125(1-0.2125)[\frac{1}{40}+\frac{1}{40}]}}$

Thus, the test statistic for the appropriate test is $\frac{0.15-0.275}{\sqrt{0.2125(1-0.2125)[\frac{1}{40}+\frac{1}{40}]}}$ .

8 0

3 years ago

Step 1: –10 + 8x < 6x – 4

Aleks04 [339]

Answer:

3 > x

Step-by-step explanation:

–2(5 – 4x) < 6x – 4

Step 1: –10 + 8x < 6x – 4

Step 2: –10 < –2x – 4

Step 3: –6 < –2x

Step 4: divide each side by by -2, remembering to flip the inequality

-6/-2 > -2/-2

3 > x

6 0

3 years ago

Read 2 more answers

What is the y-intercept of the function f(x) = 2x – 3 + 6? Round to two decimal places.

valina [46]

Y-intercept is where the graph intercepts/crosses the y-axis. So where x = 0
f(0) = 2(0) - 3 + 6
f(0) = 0 + 3
f(0) = 3
y intercept is 3
two decimal places, just add zeros
= 3.00

6 0

3 years ago

Factor this expression completely and then place the factors in the proper location on the grid. Note:

Eddi Din [679]

First we are going to group the terms that contains the common factor $m$ in one parenthesis, and the other ones in another parenthesis:
$mn-4m-5n+20$
$(mn-4m)-(5n+20)$
Notice that our the terms in our first parenthesis have a common factor $m$ , and the terms in our second one have the common factor $5$ . Lets factor those out:
$m(n-4)-5(n-4)$
Now we have a common factor $(n-4)$ in both terms, so we can factor those out as well:
$(n-4)(m-5)$

We can conclude that the completely factored expression ordered alphabetically is $(m-5)(n-4)$ .

6 0

3 years ago

Jbk111 only PLEASE 27+2,993=??

m_a_m_a [10]

3,020

fghgfdfdsdfsdfdsdfdf

7 0

3 years ago