Mathematics, 04.12.2019 02:31 Brock2002

Listed below are the lead concentrations in mug/g measured in different traditional medicines. use a 0.01 significance level to test the claim that the mean lead concentration for all such medicines is less than 17 mug/g. 13 21 3.5 18.5 21.5 8.5 15.5 19 9 5 .5

Answers: 2

Show answers

Answers

Answer from: trockout4868

$t=\frac{13.5-17}{\frac{6.57}{\sqrt{10}}}=-1.68$

$p_v =P(t_{(9)}$

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis.

We can say that at 1% of significance the mean lead concentration for all is significantly less than 17 mug/g.

Step-by-step explanation:

Data given and notation

The mean and sample deviation can be calculated from the following formulas:

$\bar X =\frac{\sum_{i=1}^n x_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (x_i -\bar X)}{n-1}}$

$\bar X=13.5$ represent the sample mean

s=6.57 represent the sample standard deviation

n=10 sample size

$\mu_o =17$ represent the value that we want to test

$\alpha=0.01$ 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)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the population mean is less than 17, the system of hypothesis are :

Null hypothesis: $\mu \geq 17$

Alternative hypothesis: $\mu < 17$

Since we don't know the population deviation, 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".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{13.5-17}{\frac{6.57}{\sqrt{10}}}=-1.68$

P-value

We need to calculate the degrees of freedom first given by:

df=n-1=10-1=9

Since is a one-side left tailed test the p value would given by:

$p_v =P(t_{(9)}$

Conclusion

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis.

We can say that at 1% of significance the mean lead concentration for all is significantly less than 17 mug/g.

Answer from: Quest

b. the decimal could be two-tenths.

step-by-step explanation:

Answer from: Quest

c. side angle side. u shares the same sides

By which rule are these triangles congruent? a) aas b) asa c) sas d) sss

Other questions on the subject: Mathematics

Mathematics, 21.06.2019 17:00, demil4257

Which of the symbols correctly relates the two numbers below check all that apply 6? 6

Answers: 2

continue

Mathematics, 21.06.2019 19:10, KaliBratz

Alogical argument that is presented in graphical form using boxes and arrows is called?

Answers: 1

continue

Mathematics, 21.06.2019 20:40, afletcher2000

If the endpoints of the diameter of a circle are (8, 6) and (2,0), what is the standard form equation of the circle? a) (x + 5)2 + (y + 3)2 = 18 (x + 5)2 + (y + 3)2 = 3.72 (x - 5)2 + (y - 3)2 = 18 d) (x - 5)2 + (y - 3)2 = 32

Answers: 1

continue

Mathematics, 21.06.2019 21:30, stressedmolly8387

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution

Answers: 2

continue

You know the right answer?

Listed below are the lead concentrations in mug/g measured in different traditional medicines. use a...