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3 years ago

What is the common ratio for the geometric sequence? 9,4, 12, 36,...

Mathematics

1 answer:

Vaselesa [24]3 years ago

5 0

Answer:

the common ratio is 0.4 repeating

Step-by-step explanation:

divide four by nine to get 0.4 repeating

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Simplify √0.08^12

MatroZZZ [7]

The only thing you could really do is reduce the exponent, so id say A. is the answer. Hope i helped :)

3 0

4 years ago

Read 2 more answers

A doctor released the results of clinical trials for a vaccine to prevent a particular disease. In these clinical trials, 400 c

Soloha48 [4]

Answer:

We conclude that the vaccine appears to be effective.

Step-by-step explanation:

We are given that a doctor released the results of clinical trials for a vaccine to prevent a particular disease.

The subjects in group 1 (the experimental group) were given the vaccine, while the subjects in group 2 (the control group) were given a placebo. Of the 200 comma 000 children in the experimental group, 38 developed the disease. Of the 200 comma 000 children in the control group, 81 developed the disease.

Let $p_1$ = proportion of subjects in the experimental group who developed the disease.

$p_2$ = proportion of subjects in the control group who developed the disease.

So, Null Hypothesis, $H_0$ : $p_1\geq p_2$ {means that the vaccine does not appears to be effective}

Alternate Hypothesis, $H_A$ : $p_1$ {means that the vaccine appears to be effective}

The test statistics that would be used here Two-sample z proportion statistics;

T.S. = $\frac{(\hat p_1-\hat p_2)-(p_1-p_2)}{\sqrt{\frac{\hat p_1(1-\hat p_1)}{n_1}+\frac{\hat p_2(1-\hat p_2)}{n_2} } }$ ~ N(0,1)

where, $\hat p_1$ = sample proportion of children in the experimental group who developed the disease = $\frac{38}{200,000}$ = 0.00019

$\hat p_2$ = sample proportion of children in the control group who developed the disease = $\frac{81}{200,000}$ = 0.00041

$n_1$ = sample of children in the experimental group = 200,000

$n_2$ = sample of children in the control group = 200,000

So, test statistics = $\frac{(0.00019-0.00041)-(0)}{\sqrt{\frac{0.00019(1-0.00019)}{200,000}+\frac{0.00041(1-0.00041)}{200,000} } }$

= -4.02

The value of z test statistics is -4.02.

Now, at 0.01 significance level the z table gives critical values of -2.33 for left-tailed test.

Since our test statistics is less than the critical value of z as -4.02 < -2.33, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the vaccine appears to be effective.

3 0

3 years ago

NEED HELP ASAP!!!

sergiy2304 [10]

14. To get the length of each side, you will have to find the square root of 189 to find what two numbers multiplied by itself will get to that number. The square root of 189 is about 13.7, to the nearest tenths is 14

7 0

3 years ago

Determine the correct set up for solving the equation using the quadratic formula 4x^2-5=3x+4

slava [35]

You need to subtract everything to the left side and set it equal to zero. Combine like terms.

Then, the coefficient of x^2 is a, the coefficient of x is b, and the constant term is c.

4x^2 - 5 = 3x + 4

4x^2 - 3x - 5 - 4 = 0

4x^2 - 3x - 9 = 0

a = 4; b = -3; c = -9

$x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}$