Estimate the value of the integral from negative 2 to 4 of x cubed, dx by using the Trapezoidal Rule with n = 3. (5 points)

A speed walker covered 4 1/2 mi in 3/4 hour. How far will he walk in 3/4 hour if he walks?

Nezavi [6.7K]

Given:

Consider the complete question is "A speed walker covered $4\dfrac{1}{4}$ mi in $\dfrac{3}{4}$ hour. How far will he walk in 3/4 hours if he walks twice as fast?"

A speed walker covered $4\dfrac{1}{4}$ mi in $\dfrac{3}{4}$ hour.

To find:

Distance covered by him if in 3/4 hour if he walks twice as fast.

Solution:

We have,

$Distance=4\dfrac{1}{2}=\dfrac{9}{2}$

It means a speed walker covered $\dfrac{9}{2}$ mi in $\dfrac{3}{4}$ hour.

If the speed is twice then he can cover double distance is same time.

Distance covered by him if in 3/4 hour if he walks twice as fast is

$2\times \dfrac{9}{2}=9$

Therefore, distance covered by him is 9 mi.

7 0

3 years ago

You have two unmarked containers, a 9-liter container and a 4-liter container, and an unlimited supply of water. Explain how you

Umnica [9.8K]

1.Fill the four liter bottle with water first.
2. pour the four liter bottle into the nine liter making the four liter bottle empty and having 4/9 in the other
3.Refill the four liter bottle
4. Pout the four liter bottle into the nine making the four again empty and the nine have 8/9
5. refill the four liter one last time.
6. Finish filling the nine liter with water from the four liter. Making the nine liter full and the four 3/4th full leaving 3 liters in the bottle.

8 0

3 years ago

An accounting professor is notorious for being stingy in giving out good letter grades. In a large section of 140 students in th

Arlecino [84]

Answer:

The 95% confidence interval for the proportion of students that obtain a letter grade of B or better from this professor is (0.2056, 0.3544). The interpretation is that we are 95% sure that the true proportion of students who obtain a letter grade of B or better from this professor is between 0.2056 and 0.3544.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

140 students, so $n = 140$

B or better are grades of A or B.

5% earn As, 23% earn Bs, so $p = 0.05 + 0.23 = 0.28$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.28 - 1.96\sqrt{\frac{0.28*0.72}{140}} = 0.2056$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.28 + 1.96\sqrt{\frac{0.28*0.72}{140}} = 0.3544$

The 95% confidence interval for the proportion of students that obtain a letter grade of B or better from this professor is (0.2056, 0.3544). The interpretation is that we are 95% sure that the true proportion of students who obtain a letter grade of B or better from this professor is between 0.2056 and 0.3544.

7 0

3 years ago

Help pleaseeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee

tamaranim1 [39]

The answer is the third one: 32 inches