What is ad over ab in it's simplest form

Evaluate the following expression when a = 5. 4a2 + a-3

crimeas [40]

4(5)2+5-3
40+5-3
45-3
42

4 0

3 years ago

Daniela is a stain glass artist; she created the window below for her living room. What is

OLga [1]

The window has a shape of a semi-circle (half of a circle).

We know the diameter d = 12 ft.

The area of a (complete) circle is given by the formula:
A = π × r²

The radius can be found by halving the diameter:
r = d ÷ 2
= 12 ÷ 2
= 6 ft

Therefore the area of the circle will be:
A = π × r²
= 3.14 × 6²
= 3.14 × 36
= 113.04 ft²

And the area of the semi-circle:
A = 113.04 ÷ 2
= 56.52 ft²

Hence, the area of the window will be 56.52 ft².

3 0

3 years ago

HURRY PLEASE Which term is like -4k? A. -4 B. -2 C. 12k

Igoryamba

Answer:

A.-4

Step-by-step explanation:

6 0

3 years ago

in a study of speed dating, male subjects were asked to rate the attractiveness of their female dates, and a sample of the res

Rudik [331]

Answer:

$7-1.796\frac{2.216}{\sqrt{12}}=5.851$

$7+1.796\frac{2.216}{\sqrt{12}}=8.149$

So on this case the 90% confidence interval would be given by (5.851;8.149)

Step-by-step explanation:

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".

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

$\mu$ population mean (variable of interest)

s represent the sample standard deviation

n represent the sample size

Solution to the problem

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

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

Data: 7 8 2 10 6 5 7 8 8 9 5 9

In order to calculate the mean and the sample deviation we can use the following formulas:

$\bar X= \sum_{i=1}^n \frac{x_i}{n}$ (2)

$s=\sqrt{\frac{\sum_{i=1}^n (x_i-\bar X)}{n-1}}$ (3)

The mean calculated for this case is $\bar X=7$

The sample deviation calculated $s=2.216$

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=12-1=11$

Since the Confidence is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.05,11)".And we see that $t_{\alpha/2}=1.796$

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

$7-1.796\frac{2.216}{\sqrt{12}}=5.851$

$7+1.796\frac{2.216}{\sqrt{12}}=8.149$

So on this case the 90% confidence interval would be given by (5.851;8.149)

3 0

3 years ago

Question 1

horsena [70]

Answer:

diameter(d)=8 in.

radius(r)= d/2= 4 in.

height(h)= 3r = 3(4) = 12 in.

Volume=r ² h

=(3.14)(4)²(12)

=(3.14)(16)(12)

=602.88 in.

Therefore, the volume of the cylinder is 602.88 in.

Step-by-step explanation:

8 0

3 years ago