I need help answering these questions, methods appreciated on how to do each one.

A machine covers 5/8 square foot in 1/4 hour

VLD [36.1K]

The question is incomplete. Here is the complete question:

A machine covers 5/8 square foot in 1/4 hour. what is the unit rate?

Answer:

2.5 square feet per hour

Step-by-step explanation:

Given:

Area covered by a machine = $frac{5}{8}\ ft^2$

Time taken to cover the given area = $\frac{1}{4}\ h$

Now, unit rate of the first quantity with respect to second quantity is the magnitude of the first quantity being when the second quantity is one unit.

Here, the first quantity is the area covered and the second quantity is the time taken.

So, unit rate is the area covered by the machine in 1 hour.

In order to find that, we use the unitary method and divide the area by the total time taken. Therefore,

$Unit\ rate=\frac{Total\ area\ covered}{Total\ time\ taken}\\\\Unit\ rate=(\frac{5}{8}\ ft^2)\div (\frac{1}{4}\ h)\\\\Unit\ rate=\frac{5}{8}\times \frac{4}{1}\ ft^2/h\\\\Unit\ rate=\frac{20}{8}=2.5\ ft^2/h$

Thus, the unit rate is 2.5 square feet per hour.

5 0

2 years ago

How do you write range on a graph?

Ratling [72]

The range of a function is the set of all possible outputs.

When the quadratic functions are in standard form, they generally look like this:

$f(x) = ax^{2} + bx + c$

If a is positive, the function opens up; if it’s negative, the function opens down. In this form, the y-coordinate of the vertex is found by evaluating f(− $\frac{b}{2a}$ ). For example, consider this function:

f(x) = $-2x^{2} + 8x -3\\$

So we’re gonna do: −b/2a=−8/2(−2)=−8/−4=2

Then, we plug this in:

$f(2) = -2(2)^{2} +8(2) -3 = 5$

a is negative, so the range is all real numbers less than or equal to 5.

Learn more about range at

brainly.com/question/2264373

#SPJ4

4 0

5 months ago

There are 4 people at a party. Consider the random variable X=’number of people having the same birthday ’ (match only month, N=

yulyashka [42]

Answer:

S = {0,2,3,4}

P(X=0) = 0.573 , P(X=2) = 0.401 , P(x=3) = 0.025, P(X=4) = 0.001

Mean = 0.879

Standard Deviation = 1.033

Step-by-step explanation:

Let the number of people having same birth month be = x

The number of ways of distributing the birthdays of the 4 men = (12*12*12*12)

The number of ways of distributing their birthdays = 12⁴

The sample space, S = { 0,2,3,4} (since 1 person cannot share birthday with himself)

P(X = 0) = $\frac{12P4}{12^{4} }$

P(X=0) = 0.573

P(X=2) = P(2 months are common) P(1 month is common, 1 month is not common)

P(X=2) = $\frac{3C2 * 12P2}{12^{4} } + \frac{4C2 * 12P3}{12^{4} }$

P(X=2) = 0.401

P(X=3) = $\frac{4C3 * 12P2}{12^{4} }$

P(x=3) = 0.025

P(X=4) = $\frac{12}{12^{4} }$

P(X=4) = 0.001

Mean, $\mu = \sum xP(x)$

$\mu = (0*0.573) + (2*0.401) + (3*0.025) + (4*0.001)\\\mu = 0.879$

Standard deviation, $SD = \sqrt{\sum x^{2} P(x) - \mu^{2}} \\SD =\sqrt{ [ (0^{2} * 0.573) + (2^{2} * 0.401) + (3^{2} * 0.025) + (4^{2} * 0.001)] - 0.879^{2}}$