Plss answer ill give brainliest pls pls

21 Last year Chelsea and Sonya took 236 pictures during Thanksgiving. This year Chelsea and Sonya each took the same amount of p

Leokris [45]

Let 'c' represent the number of pictures Chelsea took.

Let 's' represent the number of pictures Sonya took.

For last year's Thanksgiving, c + s = 236

For this year's Thanksgiving, let 'x' represent the number of photos taken in total. x = c + s, where c and s are two integers that are the same (c = s).

And we know that for both years, c + s + x = 500.

As we know that c + s is already 236 from last year, we can remove c + s from the equation in bold and replace it with 236 instead.

236 + x = 500.

Now we have to isolate the x term.

x = 500 - 236

x = 264.

We know that x = c + s, where c and s are the same, so we can just use one of the variables and double it (so you either get 2c or 2s - it doesn't matter which one you pick because they're both the same).

2c = 264

c = 132

c = s

s = 132.

Both took 132 pictures this year.

4 0

3 years ago

Evaluate y=3x for x=2. y=

11111nata11111 [884]

Answer:

y=6

Step-by-step explanation:

y=3x x=2

y=3(2)

y=6

3 0

3 years ago

What is the volume of a rectangular prism with the dimensions: base 5 8 cm, height 2 3 cm, and length 3 4 cm?

Darina [25.2K]

58 x 23 x 34 = 45356 cm³

7 0

3 years ago

Crash Hospital Costs. A study was conducts to estimate hospital costs for accident victims who wore seat belts. Twenty randomly

kvv77 [185]

Answer:

a) The 99% confidence interval would be given by (5004.168;12603.832)

b) For this case we can use the lower bound for the confidence interval as estimation, on this case 5004.168. But we need to take in count that this value it's with 99% of confidence and 1% of significance and 1% of probability to commit type Error I

Step-by-step explanation:

1) 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".

$\bar X =9004$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=5629 represent the sample standard deviation

n=20 represent the sample size

2) Part a

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:

$df=n-1=20-1=19$

Since the Confidence is 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.005,19)".And we see that $t_{\alpha/2}=2.86$

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

$9004-2.86\frac{5629}{\sqrt{20}}=5004.168$

$9004+2.86\frac{5629}{\sqrt{20}}=12603.832$

So on this case the 99% confidence interval would be given by (5004.168;12603.832)

3) Part b

For this case we can use the lower bound for the confidence interval as estimation, on this case 5004.168. But we need to take in count that this value it's with 99% of confidence and 1% of significance and 1% of probability to commit type Error I

7 0

3 years ago

Simplify -62 - 12 - 2(-7). -17 35 11 -35

nekit [7.7K]

Answer:

I got -60

I'm pretty good at this.. oop guess I missed a step

6 0

3 years ago