All categories

2 years ago

5.

1 answer:

7 0

Well, the formula for the perimeter of a rectangle is:
2l + 2w.
So, by plugging in our values of the length and width, we can easily find an answer:
length = L
width = 1 + L ( 1/3 )
2 ( L ) + 2 ( L ( 1/3 + 1 ) = 42
2l + 2/3( L ) + 2 = 42
8/3 ( L ) = 40
L = 40 * 3/8
L = 15
Therefore, the length is 15 and the width is 6.

You might be interested in

1. What is the constant rate of change between x and y in the table below?

Murljashka [212]

Answer:

Step-by-step explanation: ya boi got at least a 90 in all classes

3 0

2 years ago

Read 2 more answers

The realtor and her clients do not know the average home sale price for all of Guelph (500 was actually just a guess). However,

strojnjashka [21]

Answer:

a) The 99% confidence interval would be given by (346.708;453.292)

b) The 99% confidence interval would be given by (338.445;461.555)

Step-by-step explanation:

1) Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=400$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=80$ represent the population standard deviation

n=15 represent the sample size

2) Part a

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$

Now we have everything in order to replace into formula (1):

$400-2.58\frac{80}{\sqrt{15}}=346.708$

$400+2.58\frac{80}{\sqrt{15}}=453.292$

So on this case the 99% confidence interval would be given by (346.708;453.292)

3) Part b

For this case we don't know the population deviation so we need to use the t distribution instead the normal standard distribution.

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

We need to find the degrees of freedom first df=n-1=15-1=14

Since the Confidence is 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.005,14)".And we see that $t_{\alpha/2}=2.98$

Now we have everything in order to replace into formula (1):

$400-2.98\frac{80}{\sqrt{15}}=338.445$

$400+2.98\frac{80}{\sqrt{15}}=461.555$

So on this case the 99% confidence interval would be given by (338.445;461.555)

4 0

2 years ago

Which statement is true? Question 2 options: All parallelograms are rectangles. All rectangles are squares. All quadrilaterals a

alekssr [168]

For this case, we have that:

By definition, a rectangle is a parallelogram. So, we discard the first option.

On the other hand, we have that all rectangles can not be squares, since a square has all its sides equal, while the rectangle, poir definition, no.So, we discard the second option.

All quadrilaterals are not rectangles because there are other figures with four sides that are not necessarily rectangular. We discard the third option.

Finally, we have that all squares are rectangles. This statement is true since squares can be rectangles with pairs of equal sides.

Answer:

Option D

5 0

3 years ago

How much of an alloy with 30% copper must be added to 25 pounds of a second alloy that is 20% copper to create a 27% alloy? 33.8

yuradex [85]

Answer:

58.33 lbs.

Step-by-step explanation:

There are already 25 lbs of alloy of copper

Of this 25 lbs, 20% is pure i.e. copper content = 25(0.5) = 5lbs.

Now available is

Copper Other metals

5 lbs 20 lbs

Let x lb of 30% copper is added.

Then new alloy will have 5+0.3x lb copper in total of 25+x lbs

Percentage pure = $\frac{5+0.3x}{25+x} =27%$

Simplify to get

$\frac{5+0.3x}{25+x} =\frac{27}{100} \\\\Cross multiply:\\27(25+x) =100(5+0.3x)\\500+30x =675 +27x\\3x = 175\\x = 175/3 = 58.33 lbs$

Hence answer is 58.33 lbs should be added.

8 0

2 years ago

Read 2 more answers

Three highways connect the centers of three towns and

Vera_Pavlovna [14]

we know that

The circumcenter of a triangle is the point where the perpendicular bisectors of the sides intersect. It is also the center of the circumcircle, the circle that passes through all three vertices of the triangle

The distance of the circumcenter to the vertices of the triangle is equal to the radius of the circle

see the attached figure to better understand the problem

therefore

the answer is

The cell phone company must be place the new cell tower in the circumcenter of the triangle formed by the center of the three towns

4 0

2 years ago