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2 years ago

If it costs $4.20 per square foot to install the deck, what is the cost for plan A? Plan B?

Mathematics

1 answer:

yuradex [85]2 years ago

5 0

Answer: What does the deck look like?

Step-by-step explanation:

You might be interested in

alaska's glacier bay national had 431, 986 visitors in one year the next year the part had 22,351 more visitors than a year befo

PIT_PIT [208]

22,351 + 431,986 = 454,337

454,337 + 431,986 = 886,323

during the two years 886323 people visited

5 0

2 years ago

Consider independent simple random samples that are taken to test the difference between the means of two populations. The varia

Arturiano [62]

Answer:

d. t distribution with df = 80

Step-by-step explanation:

Assuming this problem:

Consider independent simple random samples that are taken to test the difference between the means of two populations. The variances of the populations are unknown, but are assumed to be equal. The sample sizes of each population are n1 = 37 and n2 = 45. The appropriate distribution to use is the:

a. t distribution with df = 82.

b. t distribution with df = 81.

c. t distribution with df = 41.

d. t distribution with df = 80

Solution to the problem

When we have two independent samples from two normal distributions with equal variances we are assuming that

$\sigma^2_1 =\sigma^2_2 =\sigma^2$

And the statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2}}}$

Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom and the pooled variance $S^2_p$ is given by this formula:

$\S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}$

This last one is an unbiased estimator of the common variance $\sigma^2$

So on this case the degrees of freedom are given by:

$df= 37+45-2=80$

And the best answer is:

d. t distribution with df = 80

5 0

2 years ago

Select the correct answer. Which expression is equivalent to 8x^2^3 sqrt 375x + 2^3 sqrt 3x^7, if x=0?

natima [27]

Answer:

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =28x^3\sqrt{3x}$

Step-by-step explanation:

The question is poorly formatted. The original question is:

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7$

We have:

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7$

Open bracket

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =(8^ \frac{2}{3} *x^{3* \frac{2}{3}}) \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}$

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =(8^ \frac{2}{3} *x^2) \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}$

Express 8 as 2^3

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =(2^{3* \frac{2}{3}} *x^2) \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}$

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =(2^2 *x^2) \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}$

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =4x^2 \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}$

Express 2^3 as 8

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}=4x^2 \sqrt{75x^3} + 8\sqrt{ 3x^7}$

Expand each exponent

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}=4x^2 \sqrt{25x^2 *3x} + 8\sqrt{ 3x * x^6}$

Split

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7}=4x^2 \sqrt{25x^2} *\sqrt{3x} + 8\sqrt{3x} * \sqrt{x^6}$

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =4x^2 *5x *\sqrt{3x} + 8\sqrt{3x} * x^3$

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =20x^3\sqrt{3x} + 8x^3\sqrt{3x}$

Factorize

$(8x^3)^ \frac{2}{3} \sqrt{75x^3} + 2^3 \sqrt{ 3x^7} =28x^3\sqrt{3x}$

4 0

2 years ago

Read 2 more answers

Factorise the expression: am^2 + bm^2 + bn^2+an^2

Pani-rosa [81]

Answer:

( a+b) ( m^2 + n^2)

Step-by-step explanation:

factorise like terms

m^2 ( a + b ) + n^2 ( m^2 + n^2)

then put like terms together put remaining terms in a bracket

( a + b) ( m^2 + n^2 )

6 0

2 years ago

The sum of two numbers it 226. their differences is 200. what are the numbers?

jekas [21]

To get the bigger number, divide by 2 the sum of the given sum of the numbers and their difference. In this case-
(226 + 200)/2 = 426/2 = 213.
To get the smaller number, divide by 2 the difference of the given sum of the numbers and their difference. In this case -
(226 - 200)/2 = 26/2 =13.
The two numbers are 213 and 13.
The bigger number is 213

7 0

3 years ago