Please help! I will mark as brainliest IF answer is right. <3

A random sample of 200 people was taken. 90 of the people in the sample favored Candidate A. We are interested in determining wh

mafiozo [28]

Answer:

a. 1.44

Step-by-step explanation:

We are interested in determining whether or not the proportion of the population in favor of Candidate A is significantly more than 40%.

At the null hypothesis, it is tested if the proportion is of at most 40%, that is:

$H_0: p \leq 0.4$

At the alternative hypothesis, it is tested if the proportion is of more than 40%, that is:

$H_1: p > 0.4$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

0.4 is tested at the null hypothesis:

This means that $p = 0.4, \sigma = \sqrt{0.4*0.6}$

A random sample of 200 people was taken. 90 of the people in the sample favored Candidate A.

This means that:

$n = 200, X = \frac{90}{200} = 0.45$

Value of the test statistic:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{0.45 - 0.4}{\frac{\sqrt{0.4*0.6}}{\sqrt{200}}}$

$z = 1.44$

Thus the correct answer is given by option a.

8 0

3 years ago

PLEASEEE. WIll mark brainliest

stepan [7]

Answer:

$625 (but it's really $763.14)

Step-by-step explanation:

Use the formula I=P(1+r)^t

April=25000(1.04)^5=$30416.32

May=25000(1.0375)^6=$31179.46

$31179.46-$30416.32=$763.14

So $625 is the closest answer

5 0

3 years ago

Without actual division prove that x4 +2x3 -2x2 +2x -3 is exactly divisible by x2 +2x-3

Brut [27]

Answer:

Step-by-step explanation:

$\displaystyle\Large\boldsymbol{} x^4+2x^3-2x^2+2x-3= \\\\\\x^4+2x^2(x-1)+2x-\underbrace{2-1}_{-3}= \\\\\\x^4-1+2x^2(x-1)+2x-2 = \\\\\\(x^2-1)(x^2+1)+2x^2(x-1)+2(x-1) = \\\\\\\underline{(x-1)}(x+1)(x^2+1)+2x^2\underline{(x-1)} +2\underline{(x-1)} =\\\\\\(x-1)((x+1)(x^2+1)+2x^2+2)=\\\\\\(x-1)(x^3+x^2+2x^2+x+2+1)=\\\\\\(x-1)(x^3+3x^2+x+3) =\\\\\\(x-1)( \underline{(x+3)}x^2+\underline{(x+3)})=(x^2+1)\underbrace{(x-1)(x+3)}_{x^2+2x-3}= \\\\\\(x^2+1)(x^2+2x-3) : (x^2+2x-3)=x^2+1$

7 0

3 years ago

The transformation of the function f(x) = 2x when it becomes f(x) = 2x-4 is a horizontal shift of 4 units to the left.

Natasha_Volkova [10]

No it is actually a horizontal shift of 2 units to the right.

6 0

3 years ago

Evaluate 3x² - 1 when x = 2. A. 11 B. 35 C. 3 D. 5

Alexus [3.1K]

Answer:

35

Step-by-step explanation:

All you need to do is substitute!

(3x2)^2-1

6^2-1

36-1

= 35

Hope this helps!!

4 0

2 years ago