Test Prep: Multiply the following monomials.

Which of the following inequalities is best represented by this graph?

larisa86 [58]

#3. Plugging the point (3,0) into any of the equations except the third one gives an invalid answer.

5 0

3 years ago

It takes 18 hours to fill a pool using 8 garden hoses. How long would it take to fill the same pool using 9 garden hoses?

levacccp [35]

Use rates, so 8 garden hoses over 18 hours
then find the how many hours one garden house can fill up by doing this = 18/8 you divide the 8 for both sides which is about 2.25/1
so then you times 9 which is about 20/9 hoses
your answer is 20

3 0

3 years ago

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The life span of a certain bacteria is 22 hours, with a standard deviation of 1.5 hours. In a random sampling of 5,000 bacteria,

kupik [55]

Answer:

hi!!!!!!!!!!

Step-by-step explanation:

hi!!!!!!!!!

4 0

3 years ago

A researcher finds that of 1000 people who said that they attend a religious service at least once a week, A stopped to help a p

Ne4ueva [31]

Answer:

There is enough evidence to support the claim that the proportions are not equal. (P-value: 0.048).

Step-by-step explanation:

The question is incomplete:

"A researcher finds that of 1000 people who said that they attend a religious service at least once a week, 31 stopped to help a person with car trouble. Of 1200 people interviewed who had not attended a religious service at least once a month, 22 stopped to help a person with car trouble. At the 0.05 significance level, test the claim that the two proportions are different."

This is a hypothesis test for the difference between proportions.

The claim is that the proportions are not equal.

Then, the null and alternative hypothesis are:

$H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2\neq 0$

The significance level is 0.05.

The sample 1, of size n1=1000 has a proportion of p1=0.031.

$p_1=X_1/n_1=31/1000=0.031$

The sample 2, of size n2=1200 has a proportion of p2=0.018.

$p_2=X_2/n_2=22/1200=0.018$

The difference between proportions is (p1-p2)=0.013.

$p_d=p_1-p_2=0.031-0.018=0.013$

The pooled proportion, needed to calculate the standard error, is:

$p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{31+22}{1000+1200}=\dfrac{53}{2200}=0.024$

The estimated standard error of the difference between means is computed using the formula:

$s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.024*0.976}{1000}+\dfrac{0.024*0.976}{1200}}\\\\\\s_{p1-p2}=\sqrt{0+0}=\sqrt{0}=0.007$

Then, we can calculate the z-statistic as:

$z=\dfrac{p_d-(\pi_1-\pi_2)}{s_{p1-p2}}=\dfrac{0.013-0}{0.007}=\dfrac{0.013}{0.007}=1.98$

This test is a two-tailed test, so the P-value for this test is calculated as (using a z-table):

$P-value=2\cdot P(z>1.98)=0.048$

As the P-value (0.048) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the proportions are not equal.

6 0

3 years ago

A survey was done that asked people to indicate whether they preferred to swim in a pool or in an ocean. The results are shown i

posledela

Given:
Pool swimming Ocean swimming Total
Age 30 and younger 228 54 282
Over 30 years old 142 185 327
total 370 239 609

Frequencies:
 Pool swimming Ocean swimming Total
Age 30 and younger 228/609 = 0.37 54/609 = 0.09 282/609 = 0.46
Over 30 years old 142/609 = 0.23 185/609 = 0.30 327/609 = 0.54
total 370/609 = 0.61 239/609 = 0.39 609/609 = 1.00

The relative frequency (rounded to the nearest hundredth) of a person over 30 years old who prefers to swim in the ocean is 0.30

8 0

3 years ago

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