What is the area of this figure?

The following equation has been solved incorrectly. Explain the students error

balandron [24]

On the right side of the equation, when the student combined like terms, 7x and -4x, they did not combine them correctly. Instead of combining them correctly, the student forgot to include the sign of the -4x which caused the sum of the two terms to be 11x instead of 3x. Hope this helps!

6 0

3 years ago

Read 2 more answers

Learning task 3:solve the following.....

Alexus [3.1K]

Answer:

I don't know what is this

7 0

3 years ago

You work at Dave's Donut Shop. Dave has asked you to determine how much each box of a dozen donuts should cost. There are 12 don

Archy [21]

Answer:

Donuts(b) = 12*b

Step-by-step explanation:

Notice that the question is:

What's an expression to model the number of donuts in b boxes?

We know that we are talking of boxes of a dozen donuts.

We know that in one dozen, we have 12 donuts.

Then if we have b boxes, and in each box we have 12 donuts, we will have a total of b times 12 donuts, the expression is:

Donuts(b) = 12*b

There is a lot of information here that we did not use (like the cost of cardboard and donuts), and that may be there just to distract us, the important thing to do here is:

See what is the thing we want to find (in this case, the number of donuts in b boxes)

Find the relevant information to solve this. (ignore the irrelevant information)

Solve the question.

3 0

3 years ago

Peter attends 6 dance lessons each week all year long a year has 52 weeks peter missed 5 dance lessons while sick how many dance

viktelen [127]

6 lessons per week multiplied by the number of weeks in a year
6 x 52 = 312
total - 5 missed
312 - 5 = 307 dance lessons

5 0

3 years ago

Bob Nale is the owner of Nale’s Quick Fill. Bob would like to estimate the mean number of gallons of gasoline sold to his custom

ira [324]

Answer:

a) The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

b) The 99% confidence interval would be given by (4.969;6.431)

c) We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

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".

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

$\mu$ population mean (variable of interest)

$\sigma=1.9$ represent the population standard deviation

n=45 represent the sample size

2) Part a

The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

3) Part b. Develop a 99 percent confidence interval for the population mean.

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 0.95 or 95%, 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):

$5.7-2.58\frac{1.9}{\sqrt{45}}=4.969$

$5.7+2.58\frac{1.9}{\sqrt{45}}=6.431$

So on this case the 99% confidence interval would be given by (4.969;6.431)

4) Part c. Interpret the meaning of part (b).

On this case we can say this: We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

4 0

3 years ago