Ask question

Ask question

All categories

2 years ago

13

Marni danced in a contest to raise money for an animal shelter. Marni raised $30 plus $1.80 per minute that she danced. She rais

ed a total of $264.

1 answer:

Agata [3.3K]2 years ago

7 0

Answer:

130 minutes

Step-by-step explanation:

Expression:

y = 1.80x + 30

264 = 1.80x + 30

234 = 1.8x

324/1.8 = x

130 = x

Ya Boy danced for 2 hours

You might be interested in

There are 2 computers for every 3 iPads in this technology room

qaws [65]

I’m confused on the question, what are u asking

7 0

3 years ago

Together, teammates Pedro and Ricky 2681 base hits last season. Pedro had 285 more hits than Ricky. How many hits did each playe

lara31 [8.8K]

Pedro did 1,626 hits and ricky did 1,056. Can you please help me with my question?

6 0

3 years ago

1)<br> What is the value of x?<br> 150°<br> 3x

Leona [35]

The value of x is usually 1, most of the time x is just used as a place holder

3 0

3 years ago

Slope for y=5,520.619x - 1,091.393

Bad White [126]

Answer:

m = 5,520.619

Step-by-step explanation:

The given equation is :

y=5,520.619x-1,091.393 ....(1)

The general form of equation is given by :

y = mx +c ...(2)

Where

m is slope of line

c is y-intercept

Comparing equation (1) and (2), we get :

Slope, m = 5,520.619

Hence, the slope of the given line is 5,520.619.

3 0

3 years ago

We considered the differences between the temperature readings in January 1 of 1968 and 2008 at 51 locations in the continental

mr Goodwill [35]

Answer:

$1.1-2.02\frac{4.9}{\sqrt{50}}=-0.30$

$1.1+2.02\frac{4.9}{\sqrt{50}}=2.50$

So on this case the 90% confidence interval would be given by (-0.30;2.50)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=1.1$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=4.9 represent the sample standard deviation

n=51 represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=51-1=50$

Since the Confidence is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.05,50)".And we see that $t_{\alpha/2}=2.02$

Now we have everything in order to replace into formula (1):

$1.1-2.02\frac{4.9}{\sqrt{50}}=-0.30$

$1.1+2.02\frac{4.9}{\sqrt{50}}=2.50$

So on this case the 90% confidence interval would be given by (-0.30;2.50)

8 0

3 years ago