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2 years ago

5

An artist wants to paint 15 pictures in three months she only starts a new picture when she is done with the previous one use re

peated subtraction to show how many pictures she has to paint each month

1 answer:

gladu [14]2 years ago

4 0

Answer: 5

Step-by-step explanation: 15/3 is 5

You might be interested in

A safety officer wants to prove that μ = the average speed of cars driven by a school is less than 25 mph. Suppose that a random

Akimi4 [234]

Answer:

$t=\frac{24-25}{\frac{2.2}{\sqrt{14}}}=-1.70$

The degrees of freedom are given by:

$df=n-1=14-1=13$

The p value for this case would be given by:

$p_v =P(t_{(13)}$

Step-by-step explanation:

Information given

$\bar X=24$ represent the mean height for the sample

$s=2.2$ represent the sample standard deviation

$n=14$ sample size

$\mu_o =25$ represent the value that we want to test

t would represent the statistic

$p_v$ represent the p value for the test

Hypothesis to verify

We want to cehck if the true mean is lees than 25 mph, the system of hypothesis would be:

Null hypothesis: $\mu \geq 25$

Alternative hypothesis: $\mu < 25$

The statistic would be given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

Replacing the info given we got:

$t=\frac{24-25}{\frac{2.2}{\sqrt{14}}}=-1.70$

The degrees of freedom are given by:

$df=n-1=14-1=13$

The p value for this case would be given by:

$p_v =P(t_{(13)}$

8 0

2 years ago

Data from 14 cities were combined for a 20-year period, and the total 280 city-years included a total of 107 homicides. After

leonid [27]

Answer:

P(0) = 0.6825

P(1) = 0.2607

Step-by-step explanation:

From the given information, the number of homicide is 107 and the total number of homicides per city –year is 280.

Let us denote the number of homicides per city-year as X.

The mean value, X is calculated as:

\begin{array}{c}\\{\rm{Mean}} = \frac{{107}}{{280}}\\\\ = 0.382\\\end{array}

Mean= 107/280 = 0.382

The mean number of homicides per city- year \left( {\lambda = \mu } \right)(λ=μ) is 0.382.

a. The probability that zero homicides is obtained is as below:

\begin{array}{c}\\P\left( {X = 0} \right) = \frac{{{e^{ -0.382}}{{\left( {0.382} \right)}^0}}}{{0!}}\\\\ = \frac{{\left( {0.6825 \right)\left( {\rm{1}} \right)}}{1}\\\\ = 0.6825\\\end{array}

P(X=0) = e −0.382 (0.382)⁰/1

= (0.6825)(1) /1

P(X=0) = 0.6825

Thus, the probability that zero homicides P(0) is 0.6825.

b. The probability that one homicides is obtained is as below:

\begin{array}{c}\\P\left( {X = 0} \right) = \frac{{{e^{ -0.382}}{{\left( {0.382} \right)}^0}}}{{0!}}\\\\ = \frac{{\left( {0.6825 \right)\left( {\rm{1}} \right)}}{1}\\\\ = 0.6825\\\end{array}

P(X=1) = e −0.382 (0.382)¹/1

= (0.6825)(0.382)/1

P(X=1) = 0.2607

Thus, the probability that zero homicides P(0) is 0.2607.

5 0

2 years ago

In 2015, in Buffalo, New York, there were 8,625 arrests, 2,678 robberies, 865 assaults, and 20 murders. The population of Buffal

m_a_m_a [10]

I'm pretty sure simplest form would still be 865:2678
I could be wrong tho

6 0

2 years ago

Read 2 more answers

Suppose the time it takes a barber to complete a haircuts is uniformly distributed between 8 and 22 minutes, inclusive. Let X =

salantis [7]

Answer:

$P(X>14)= 1-P(X$

And replacing we got:

$P(X>14)= 1- \frac{14-8}{22-8}= 0.5714$

The probability that a randomly selected barber needs at least 14 minutes to complete the haircut is 0.5714

Step-by-step explanation:

We define the random variable of interest as x " time it takes a barber to complete a haircuts" and we know that the distribution for X is given by:

$X \sim Unif (a= 8, b=22)$

And for this case we want to find the following probability:

$P(X>14)$

We can find this probability using the complement rule and the cumulative distribution function given by:

$P(X$

Using this formula we got:

$P(X>14)= 1-P(X$

And replacing we got:

$P(X>14)= 1- \frac{14-8}{22-8}= 0.5714$

The probability that a randomly selected barber needs at least 14 minutes to complete the haircut is 0.5714

6 0

2 years ago

Consider the function f(x) = x3 − 4x2 + 2. Calculate the limit of the difference quotient at x0 = 3 for f(x).

m_a_m_a [10]

<h2>Part 1.</h2>

Answer: $\boxed{f'(x)=3x^2-8x}$

The limit of the difference quotient is simply the derivative, so we can express this as follows:

$f'(x)=\underset{\Delta x\rightarrow0}{lim}\frac{\triangle y}{\Delta x}=\frac{f(x+\Delta x)-f(x)}{\Delta x}$

So our function is:

$f(x)=x^3-4x^2+2$

Taking the derivative, we have:

$f'(x)=3x^2-8x$

So the correct option is:

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

<h2>Part 2.</h2>

Answer: $\boxed{y=3x-16}$

The equation of the line that passes through the same point can be found as:

$y-y_{0}=m(x-x_{0})$

Where $x_{0}=3$ , so we need to find $y_{0}$ . Plug in that x-value in the function we have:

$y_{0}=f(3)=(3)^3-4(3)^2+2 \\ \\ y_{0}=-7 \\ \\ \\ So \ the \ point \ is: \\ \\ P(x_{0},y_{0})=(3,-7)$

And the slope is:

$m=f'(3)=3(3)^2-8(3) \\ \\ m=3$

Then, the equation of the line is:

$y-(-7)=3(x-3) \\ \\ \therefore y+7=3x-9 \\ \\ \boxed{y=3x-16}$

<h2 /><h2>Part 3.</h2>

Answer: Shown below

As you can see below, the graph of the function of $f$ is continuous. This is so because we have plotted a polynomial function whose domain is the set of all real numbers. So the function is defined at the point $P(3,-7)$ , so the derivative exists at this point, hence we can calculate a tangent line there. In conclusion, we get the graph shown below. The blue line is the tangent line while the red curve is the graph of $f$

3 0

2 years ago