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3 years ago

13

Express the area of the entire rectangle. Your answer should be a polynomial in standard form.

1 answer:

lyudmila [28]3 years ago

4 0

Answer:

x^2 + 12x + 27

Step-by-step explanation:

x^2 + 9x + 3x + 27 =

= x^2 + 12x + 27

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A number written using only words is written using a

Blababa [14]

Answer:

i genuinlly dont know what you mean

Step-by-step explanation:

5 0

2 years ago

Find the perimeter of a parallelogram whose base is 8cm and another side is 12cm

lidiya [134]

A parallelogram

P=2(a+b)

The answer is 64

P=2(a+b)=2·(24+8)=64

6 0

3 years ago

The following results come from two independent random samples taken of two populations.

photoshop1234 [79]

Answer:

$(a)\ \bar x_1 - \bar x_2 = 2.0$

$(b)\ CI =(1.0542,2.9458)$

$(c)\ CI = (0.8730,2.1270)$

Step-by-step explanation:

Given

$n_1 = 60$ $n_2 = 35$

$\bar x_1 = 13.6$ $\bar x_2 = 11.6$

$\sigma_1 = 2.1$ $\sigma_2 = 3$

Solving (a): Point estimate of difference of mean

This is calculated as: $\bar x_1 - \bar x_2$

$\bar x_1 - \bar x_2 = 13.6 - 11.6$

$\bar x_1 - \bar x_2 = 2.0$

Solving (b): 90% confidence interval

We have:

$c = 90\%$

$c = 0.90$

Confidence level is: $1 - \alpha$

$1 - \alpha = c$

$1 - \alpha = 0.90$

$\alpha = 0.10$

Calculate $z_{\alpha/2}$

$z_{\alpha/2} = z_{0.10/2}$

$z_{\alpha/2} = z_{0.05}$

The z score is:

$z_{\alpha/2} = z_{0.05} =1.645$

The endpoints of the confidence level is:

$(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}$

$2.0 \± 1.645 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}$

$2.0 \± 1.645 * \sqrt{\frac{4.41}{60}+\frac{9}{35}}$

$2.0 \± 1.645 * \sqrt{0.0735+0.2571}$

$2.0 \± 1.645 * \sqrt{0.3306}$

$2.0 \± 0.9458$

Split

$(2.0 - 0.9458) \to (2.0 + 0.9458)$

$(1.0542) \to (2.9458)$

Hence, the 90% confidence interval is:

$CI =(1.0542,2.9458)$

Solving (c): 95% confidence interval

We have:

$c = 95\%$

$c = 0.95$

Confidence level is: $1 - \alpha$

$1 - \alpha = c$

$1 - \alpha = 0.95$

$\alpha = 0.05$

Calculate $z_{\alpha/2}$

$z_{\alpha/2} = z_{0.05/2}$

$z_{\alpha/2} = z_{0.025}$

The z score is:

$z_{\alpha/2} = z_{0.025} =1.96$

The endpoints of the confidence level is:

$(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}$

$2.0 \± 1.96 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}$

$2.0 \± 1.96* \sqrt{\frac{4.41}{60}+\frac{9}{35}}$

$2.0 \± 1.96 * \sqrt{0.0735+0.2571}$

$2.0 \± 1.96* \sqrt{0.3306}$

$2.0 \± 1.1270$

Split

$(2.0 - 1.1270) \to (2.0 + 1.1270)$

$(0.8730) \to (2.1270)$

Hence, the 95% confidence interval is:

$CI = (0.8730,2.1270)$

8 0

3 years ago

g The manager of a grocery store has selected a random sample of 100 customers. The average length of time it took these 100 cus

vagabundo [1.1K]

Answer:

The right solution is "0.196".

Step-by-step explanation:

The given values are:

Standard deviation,

$\sigma=1 \ minute$

Sample size,

$n=100$

Confidence level,

$c=95$ %

$=0.95$

Now,

For $\alpha=1-c$

$= 1-0.95$

$=0.05$

then,

$Z_{\frac{\alpha}{2} } = Z_{\frac{0.05}{2} }$

$=Z_{0.025}$

$=1.96$

The margin or error will be:

⇒ $E=Z_{\frac{\alpha}{2} } (\frac{\sigma}{\sqrt{n} })$

On substituting the values, we get

= $1.96(\frac{1}{\sqrt{100} })$

= $1.96\times \frac{1}{10}$

= $0.196$

7 0

3 years ago

Please help! (Numbers 1 and 2)

Svetradugi [14.3K]

1. is 8
2. is 4

Subtract them by the percentage

5 0

3 years ago