All categories

3 years ago

She runs at a speed of 7 miles per hour for 11.2 miles. for how many hours does she run?

1 answer:

8 0

To answer this problem, given the speed is 7mph and the distance is 11.2mile and its obvious that we can divide the given distance by the speed. The answer is 11.2/7= 1.6 hours

You might be interested in

Pam has 90 m of fencing to enclose an area in a petting zoo with two dividers to separate three types of young animals. The thre

andrew-mc [135]

Answer:

The area function is

$A=\frac{135}{2}x-\frac{9}{2}x^2$ .

The domain and range of A is $(0,15m)$ and $(0, 253.125 m^2]$ .

Step-by-step explanation:

The given length of fencing is $90 m$ .

Let the length and width of each pen be $x$ and $y$ respectively as shown in the figure.

As there are 3 pens, so, the total area,

$A= 3 xy \;\cdots (i)$

From the figure the total length of fencing is $6x+4y$ .

Here, for a significant area for the animals, $x>0$ as well as $y>0$ as $x$ and $y$ are the sides of ben.

From the given value:

$6x+4y=90\;\cdots (ii)$

$\Rightarrow y=\frac {45}{2}-\frac{3x}{2}$

Now, from equation (i)

$A=3x\left(\frac {45}{2}-\frac{3x}{2}\right)$

$\Rightarrow A=\frac{135}{2}x-\frac{9}{2}x^2\;\cdots (iii)$

This is the required area function in the terms of variable $x$ .

For the domain of area function, from equation (ii)

$x=15-\frac{2y}{3}$

$\Rightarrow x$ [as y>0]

So, the domain of area function is $(0,15m)$ .

For the range of area function:

As $x \rightarrow 0$ or $y\rightarrow 0$ , then $A\rightarrow 0$ [from equation (i)]

$\Rightarrow A>0$

Now, differentiate the area function with respect to $x$ .

$\frac {dA}{dx}=\frac{135}{2}-9x$

Equate $\frac {dA}{dx}$ to zero to get the extremum point.

$\frac {dA}{dx}=0$

$\Rightarrow \frac{135}{2}-9x=0$

$\Rightarrow x=\frac{15}{2}$

Check this point by double differentiation

$\frac {d^2A}{dx^2}=-9$

As, $\frac {d^2A}{dx^2}$ , so, point $x=\frac{15}{2}$ is corresponding to maxima.

Put this value back to equation (iii) to get the maximum value of area function. We have

$A=\frac{135}{2}\times \frac {15}{2}-\frac{9}{2}\times \left(\frac {15}{2}\right)^2$

$\Rightarrow A=253.125 m^2$

Hence, the range of area function is $(0, 253.125 m^2]$ .

4 0

3 years ago

The dot product of u with itself is 24. what is the magnitude of u? 2sqrt 3 2sqrt 6 12 24

My name is Ann [436]

Hat do you know someone called English

6 0

3 years ago

Find the modal class interval.

photoshop1234 [79]

Answer: 24≤ a < 26

Step-by-step explanation:

The modal class interval is the class interval with the highest frequency, the highest frequency from the table is 8 , which belongs to the class interval 24≤ a < 26

4 0

3 years ago

Plz guys help me In 2 please

Doss [256]

Answer:

Step-by-step explanation:

OMG!!!!! why don't you just SAY YOU WANT a BLEEPING REFLECTION!!!

I had to search through a slew of your questions to get clues as to what to do.

To reflect over the x axis, just negate the y term and leave the x term as it is.

M becomes (2, -1)

N becomes (-3, -1)

P becomes (-1, -4)

7 0

2 years ago

The equation y ̂=844.697x^2+3723.485x-13,650 models the annual profits of a new business, where x is the number of years since t

julsineya [31]

The answer is $37,923

<span>y = 844.697x^2 + 3723.485x - 13,650
x - number of years
y - the annual profit

If x = 8, the annual profit y is:
y = </span>844.697 * 8^2 + 3723.485 * 8 - 13,650
y = 844.697 * 64 + 29,787.88 - 13,650
y = 54,060.608 + 16,137.88
y = 37,922.728 ≈ 37,923

5 0

3 years ago