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3 years ago

7

Bob works at a construction company. He has an equally likely chance to be assigned

1 answer:

Nadusha1986 [10]3 years ago

8 0

Answer:

$7$ <em>times.</em>

Step-by-step explanation:

We know that there are three buildings that he can be assigned to.

Since there are three buildings, the probability of each crew would be $\frac{1}{3}$ .

If you set up the proportion, it would look like this.

$\frac{1}{3}$ = $\frac{x}{21}$

The next step would be to solve for x.

$3x =21$

$x=7$

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Does this set of ordered pairs represent a function? Why or why not. Don’t need a step to step just the answer

Scrat [10]

Answer:

D. Yes,because every x-value corresponds to exactly one y-value.

Step-by-step explanation:

The given ordered pairs are;

{ $(-5,-5),(-1,-2),(0,-2),(3,7),(8,9)$ }

We do not have the same x-value corresponding to more than one y-value.

We can see from the ordered pairs that every x-value corresponds to exactly one y-value.

Therefore the graph of this relation will pass the vertical line test.

3 0

3 years ago

Read 2 more answers

The estimated daily living costs for an executive traveling to various major cities follow. The estimates include a single room

Alexandra [31]

Answer:

$\bar x = 260.1615$

$\sigma = 70.69$

The confidence interval of standard deviation is: $53.76$ to $103.25$

Step-by-step explanation:

Given

$n =20$

See attachment for the formatted data

Solving (a): The mean

This is calculated as:

$\bar x = \frac{\sum x}{n}$

So, we have:

$\bar x = \frac{242.87 +212.00 +260.93 +284.08 +194.19 +139.16 +260.76 +436.72 +355.36 +.....+250.61}{20}$

$\bar x = \frac{5203.23}{20}$

$\bar x = 260.1615$

$\bar x = 260.16$

Solving (b): The standard deviation

This is calculated as:

$\sigma = \sqrt{\frac{\sum(x - \bar x)^2}{n-1}}$

$\sigma = \sqrt{\frac{(242.87 - 260.1615)^2 +(212.00- 260.1615)^2+(260.93- 260.1615)^2+(284.08- 260.1615)^2+.....+(250.61- 260.1615)^2}{20 - 1}}$ $\sigma = \sqrt{\frac{94938.80}{19}}$

$\sigma = \sqrt{4996.78}$

$\sigma = 70.69$ --- approximated

Solving (c): 95% confidence interval of standard deviation

We have:

$c =0.95$

So:

$\alpha = 1 -c$

$\alpha = 1 -0.95$

$\alpha = 0.05$

Calculate the degree of freedom (df)

$df = n -1$

$df = 20 -1$

$df = 19$

Determine the critical value at row $df = 19$ and columns $\frac{\alpha}{2}$ and $1 -\frac{\alpha}{2}$

So, we have:

$X^2_{0.025} = 32.852$ ---- at $\frac{\alpha}{2}$

$X^2_{0.975} = 8.907$ --- at $1 -\frac{\alpha}{2}$

So, the confidence interval of the standard deviation is:

$\sigma * \sqrt{\frac{n - 1}{X^2_{\alpha/2} }$ to $\sigma * \sqrt{\frac{n - 1}{X^2_{1 -\alpha/2} }$

$70.69 * \sqrt{\frac{20 - 1}{32.852}$ to $70.69 * \sqrt{\frac{20 - 1}{8.907}$

$70.69 * \sqrt{\frac{19}{32.852}$ to $70.69 * \sqrt{\frac{19}{8.907}$

$53.76$ to $103.25$

8 0

2 years ago

How do you find 65% of 100

galben [10]

You multiply .65 times 100 and you get 65 which is 65% of 100

7 0

3 years ago

Read 2 more answers

Whats the area of the shaded region

barxatty [35]

Answer:

36 meter square

<h2>Please mark my answer as brainliest for further answers:)</h2>

4 0

3 years ago

Many insects migrate (travel) between their summer and winter homes. The desert locust migrates about 800 miles farther than the

Harman [31]

Answer:

Distance travelled by Monarch butterfly = 2000 miles

Distance travelled by desert locust = 2800

Distance travelled by pink-spotted hawk moth= 7800 miles

Step-by-step explanation:

Let the distance travelled by Monarch butterfly be "X" miles

Distance travelled by desert locust is equal to X + 800 miles

Distance travelled by pink-spotted hawk moth is equal to 4X -200 miles

The total distance travelled by the three is equal to 12600 miles

$X + X + 800 + 4X -200 = 12600\\6X = 12600 -600\\6X = 12000\\X = 2000$

Distance travelled by Monarch butterfly = 2000 miles

Distance travelled by desert locust = 2000 + 800 = 2800

Distance travelled by pink-spotted hawk moth = 4 * 2000 -200 = 7800 miles

6 0

3 years ago