Use 3.14 for and do not round your answer. Be sure to indude the correct unit in your answer.

Out of 32 students in a class, 5 said they ride their bikes to school. based on these results,how many of 800 students in the sc

Colt1911 [192]

Do a proportion.
5/32= x/800
Cross multiply and divide
800 x 5= 4,000
4,000 divided by 32= 125
So answer is 125 students

6 0

3 years ago

Find the standard form of the equation for the circle with the following properties.

nataly862011 [7]

Answer:

$(x+6)^2+(y+\frac{7}{6})^2=\frac{49}{36}$

Step-by-step explanation:

So, we know that the center of the circle is at (-6, -7/6).

To find the equation of our circle that is tangent to the x-axis, we just need to find the vertical distance from our center to the x-axis.

Our center is at (-6, -7/6). The vertical distance from this to the x-axis directly above will be (-6, 0).

So, find our distance by subtracting our x-values:

$d=r=0-(-7/6)$

Subtract:

$d=r=7/6$

So, our distance, which is also our radius, will be 7/6.

Now, we can use the standard form for a circle, which is:

$(x-h)^2+(y-k)^2=r^2$

Where (h, k) is the center and r is the radius.

Substitute -6 for h, -7/6 for k, and 7/6 for r. This yields:

$(x+6)^2+(y+\frac{7}{6})^2=\frac{49}{36}$

We can confirm by graphing (using a calculator):

7 0

3 years ago

. (0.5 point) We simulate the operations of a call center that opens from 8am to 6pm for 20 days. The daily average call waiting

SashulF [63]

Answer:

The 95% t-confidence interval for the difference in mean is approximately (-2.61, 1.16), therefore, there is not enough statistical evidence to show that there is a change in waiting time, therefore;

The change in the call waiting time is not statistically significant

Step-by-step explanation:

The given call waiting times are;

24.16, 20.17, 14.60, 19.79, 20.02, 14.60, 21.84, 21.45, 16.23, 19.60, 17.64, 16.53, 17.93, 22.81, 18.05, 16.36, 15.16, 19.24, 18.84, 20.77

19.81, 18.39, 24.34, 22.63, 20.20, 23.35, 16.21, 21.73, 17.18, 18.98, 19.35, 18.41, 20.57, 13.00, 17.25, 21.32, 23.29, 22.09, 12.88, 19.27

From the data we have;

The mean waiting time before the downsize, $\overline x_1$ = 18.7895

The mean waiting time before the downsize, s₁ = 2.705152

The sample size for the before the downsize, n₁ = 20

The mean waiting time after the downsize, $\overline x_2$ = 19.5125

The mean waiting time after the downsize, s₂ = 3.155945

The sample size for the after the downsize, n₂ = 20

The degrees of freedom, df = n₁ + n₂ - 2 = 20 + 20 - 2 = 38

df = 38

At 95% significance level, using a graphing calculator, we have; $t_{\alpha /2}$ = ±2.026192

The t-confidence interval is given as follows;

$\left (\bar{x}_{1}- \bar{x}_{2} \right )\pm t_{\alpha /2}\sqrt{\dfrac{s_{1}^{2}}{n_{1}}+\dfrac{s_{2}^{2}}{n_{2}}}$

Therefore;

$\left (18.7895- 19.5152 \right )\pm 2.026192 \times \sqrt{\dfrac{2.705152^{2}}{20}+\dfrac{3.155945^2}{20}}$

(18.7895 - 19.5125) - 2.026192*(2.705152²/20 + 3.155945²/20)^(0.5)

The 95% CI = -2.6063 < μ₂ - μ₁ < 1.16025996668

By approximation, we have;

The 95% CI = -2.61 < μ₂ - μ₁ < 1.16

Given that the 95% confidence interval ranges from a positive to a negative value, we are 95% sure that the confidence interval includes '0', therefore, there is sufficient evidence that there is no difference between the two means, and the change in call waiting time is not statistically significant.

6 0

2 years ago

Help please !!!!!!???

Alona [7]

Answer:

hiiiiiiiii

Step-by-step explanation:

3 0

3 years ago

How many flowers, spaced every 3 in., are needed to surround a circular garden with a 150-ft radius? Use 3.14 for pi.

BARSIC [14]

Answer: