ASAP FOR BRAINIEST AND MANY POINTS

Find an explicit rule for the nth term of the sequence.

taurus [48]

Answer: -4 . 2ⁿ⁻¹

Step-by-step explanation: This is a geometric progression

the nth term is given by arⁿ⁻¹

a = the first term of the sequence

r = common ratio

n= number of terms

for this sequence

a = -4

r = -8/-4 = 2

nth term, an = -4 . 2ⁿ⁻¹

3 0

3 years ago

Based on historical data in Oxnard college, we believe that 37% of freshmen do not visit their counselors regularly. For this ye

slega [8]

Answer:

A sample size of 1031 is required.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is of:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

37% of freshmen do not visit their counselors regularly.

This means that $\pi = 0.37$

98% confidence level

So $\alpha = 0.02$ , z is the value of Z that has a pvalue of $1 - \frac{0.02}{2} = 0.99$ , so $Z = 2.327$ .

You would like to be 98% confident that your estimate is within 3.5% of the true population proportion. How large of a sample size is required?

A sample size of n is required.

n is found when M = 0.035. So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.035 = 2.327\sqrt{\frac{0.37*0.63}{n}}$

$0.035\sqrt{n} = 2.327\sqrt{0.37*0.63}$

$\sqrt{n} = \frac{2.327\sqrt{0.37*0.63}}{0.035}$

$(\sqrt{n})^2 = (\frac{2.327\sqrt{0.37*0.63}}{0.035})^2$

$n = 1030.4$

Rounding up:

A sample size of 1031 is required.

4 0

3 years ago

What kind of equations have the greatest outputs?

stepladder [879]

Answer:

Exponential

Step-by-step explanation:

8 0

3 years ago

One base of a trapezoid is five times as long as the other. The height is the average of the two bases. The area is 441 square u

Gelneren [198K]

Answer:

The length of the longer base he 35 units

Step-by-step explanation:

Here, we want to find the length of the longer base of the trapezoid

Mathematically, we can find the area using the formula;

1/2( a + b) h

where a is the shorter base

b is the longer base

h is the height

Let the shorter base be x

The other base is 5 times this length and that makes 5 * x = 5x

Height is the average of both bases;

(x + 5x)/2 = 6x/2 = 3x

Substituting these in the formula, we have ;

1/2(x + 5x)3x = 441

3x(6x) = 882

18x^2 = 882

x^2 = 882/18

x^2 = 49

x^2 = 7^2

x = 7

But the longer base is 5x and that will be 5 * 7 = 35 units

4 0

3 years ago

An insurance company sells automobile liability and collision insurance. Let X denote the percentage of liability policies that

qaws [65]

Answer:

-764.28

Step-by-step explanation:

Given the joint cumulative distribution of X and Y as

$F(x,y) = \frac{xy(x+y)}{2000000}\ \ \ \, \ 0\leq x100, 0\leq y\leq 100$

#First find $F_x$ and probability distribution function , $f_x(x)$ :

$F_x(x)=F(x,100)\\\\\\=\frac{100x(x+100)}{2000000}\\\\\\\\=\frac{100x^2+10000x}{2000000}\\\\\\=>f_x(x)=\frac{x}{10000}+\frac{1}{200}$

#Have determined the probability distribution unction , $f_x(x)$ , we calculate the Expectation of the random variable X:

$E(X)=\int\limits^{100}_0 \frac{x^2}{10000}+\frac{x}{200} dx \\\\\\\\=|\frac{x^3}{30000}+\frac{x^2}{400}|\limits^{100}_0\\\\=58.33\\\\$

#We then calculate $E(X^2)$ :

$E(X^2)=\int\limits^{100}_0 \frac{x^3}{10000}+\frac{x^2}{200}\ dx\\\\=\frac{x^4}{40000}+\frac{x^3}{600}|\limits^{100}_0=4166.67\\\\Var(X)=E(X^2)-(E(X))^2=4166.67-58.33^2\\\\Var(X)=764.28$

Hence, the Var(X) is 764.28

4 0

3 years ago