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3 years ago

Use geometric mean to find the 7th term in a geometric sequence if the 6th term is 12 and the 8th term is 27

Mathematics

1 answer:

Darya [45]3 years ago

3 0

Answer:

Step-by-step explanation:

<em>First, use the equation for geometric mean; an=a1r^n-1</em>

*where is an is the number at an n term, r is the ratio and a1 is the first number of the sequence.*

12 = a1 r^5

27 = a1r^7

From the equations above,

a1 = 128/81

r = 3/2

Therefore, the 7th term is:

an = (128/81) (3/2)^6

an = 18

hope this helps :)

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The government of Preon (a small island nation) was voted in at the last election with 58% of the votes. That was 2 years ago, a

mel-nik [20]

Answer:

a) $z=\frac{0.684 -0.58}{\sqrt{\frac{0.58(1-0.58)}{114}}}=2.250$

b) $p_v =2*P(z>2.250)=0.0244$

If we compare the p value and the significance level given we see that $p_v$ we have enough evidence to reject the null hypothesis at 5% of significance.

Step-by-step explanation:

Data given and notation

n=114 represent the random sample taken

$\hat p=0.684$ estimated proportion of people that their approval rating might have changed

$p_o=0.58$ is the value that we want to test

$\alpha=0.05$ represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Hypothesis

We need to conduct a hypothesis in order to test the claim that true proportion of people that their approval rating might have changed is 0.58 or no.:

Null hypothesis: $p=0.58$

Alternative hypothesis: $p \neq 0.58$

Part a

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.684 -0.58}{\sqrt{\frac{0.58(1-0.58)}{114}}}=2.250$

Part b: Statistical decision

The significance level provided $\alpha=0.05$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(z>2.250)=0.0244$

If we compare the p value and the significance level given we see that $p_v$ we have enough evidence to reject the null hypothesis at 5% of significance.

7 0

3 years ago

Simplify (x+2)(x+6) using grouping, and write the resulting expression in standard form

Vlad1618 [11]

Answer:

(x+8)

Step-by-step explanation:

8 0

3 years ago

4x + 5y = 12 and 3x + 4y = 9.25 . Solve for systems of equations

masha68 [24]

Answer:

y=1

x=7/4

Step-by-step explanation:

4x + 5y = 12

3x + 4y = 9.25

4x + 5y = 12

12x + 16y =37

-12x -15 y =-36

12x + 16y =37

y=1

x=7/4

8 0

3 years ago

Read 2 more answers

What is the slope of this line?

Lynna [10]

$\frac{ - 2}{2}$

8 0

3 years ago

In a group of equal number of men and women 10% men and 45% women are suffering from Malaria.What is probability a peraon select

Kaylis [27]

Answer:

The probability a person selected random is not suffering from Malaria is 0.725.

Step-by-step explanation:

Denote the events as follows:

X = a person is suffering from Malaria

M = a man

W = a woman

The information provided is:

P (M) = P (W) = 0.50

P (X|M) = 0.10

P (X|W) = 0.45

Compute the probability a person selected random is suffering from Malaria as follows:

$P(X)=P(X|M)P(M)+P(X|W)P(W)$

$=(0.10\times 0.50)+(0.45\times 0.50)\\\\=0.05+0.225\\\\=0.275$

Then the probability a person selected random is not suffering from Malaria is:

P (X') = 1 - P (X)

= 1 - 0.275

= 0.725

4 0

3 years ago