Analyze the number line below and answer the question that follows

Lynne is driving at a constant rate of 48 miles per hour.how far will she drive in 4 hours

Kryger [21]

48*4=192mph

Answer is 192mph

7 0

2 years ago

The speeds of vehicles traveling on a highway are normally distributed with an unkown population mean and standard deviation. A

Maksim231197 [3]

Answer:

The 90% confidence interval would be given by (60.09;69.91)

We are 90% confident that the true mean for the speeds of vehicles traveling on a highway is between 60.09 and 69.91 miles per hour.

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".

$\bar X =65$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=9 represent the sample standard deviation

n=11 represent the sample size

2) Confidence interval

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

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

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

$df=n-1=11-1=10$

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(0.05,10)".And we see that $t_{\alpha/2}=1.81$

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

$65-1.81\frac{9}{\sqrt{11}}=60.09$

$65+1.81\frac{9}{\sqrt{11}}=69.91$

So on this case the 90% confidence interval would be given by (60.09;69.91)

We are 90% confident that the true mean for the speeds of vehicles traveling on a highway is between 60.09 and 69.91 miles per hour.

3 0

2 years ago

PLEASE HELP ME AND MY FRIEND NEED THIS QUESTION ANSWERED PLEASE HELP

Bas_tet [7]

Answer:

$V_{cone} =65.94\: cm^3$

Step-by-step explanation:

Height of cone (h) = 7 cm

Base radius (r) = 3 cm

Formula for Volume of cone is given as:

$V_{cone} = \frac{1}{3}\pi r^2h$

Plugging the values of h and r in the above formula, we find:

$V_{cone} = \frac{1}{3}(3.14) (3)^2(7)$

$\implies V_{cone} = \frac{1}{\cancel 3}(3.14) (\cancel 9)(7)$

$\implies V_{cone} = (3.14) (3)(7)$

$\implies V_{cone} =65.94\: cm^3$

7 0

1 year ago

What us the difference in the ares of a circle with diameter 4 m and a circle with diameter 6 m? Round your answer to the neares

enyata [817]

Let's calculate each area.
4 m:
We need to divide it by 2 to find the radius.
4÷2=2
Now let's put it in the formula.
2²π
4π=12.5663706≈13
6 m:
We need to divide it by 2 for the radius.
6÷2=3
Now put it in the formula.
3²π
9π=28.2743≈28
Now subtract 13 from 28.
28-13=15
So, the difference between their area is 15 m².

6 0

3 years ago

Timothy is an hourly employee and he can work maximum of 40 hours in a week. If the weekly salary depends on the number of hours

Gennadij [26K]

Answer:

C

Step-by-step explanation:

0 ≤ h ≤ 40, h ∈ R

Hope this helps :)

7 0

2 years ago