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3 years ago

Every day, the number of network blackouts has a distribution (probability mass function)

1 answer:

3 0

Expected Mean, E(X), is obtained by multiplying each pair of $x$ and its $P(x)$ and add up the answers

E(X) = (0×0.7) + (1×0.2) + (2×0.1) = 0.4

The formula to calculate the variance, Var(X), is given by E(X)² - (E(X))²

E(X²) = (0²×0.7) + (1²×0.2) + (2²×0.1) = 0+0.2+0.4 = 0.6
(E(X))² = (0.4)² = 0.16

Var(X) = 0.6 - 0.16 = 0.44

Translating these answers into the context we have

E(Y) = 0.4×500 = $200
Var(Y) = $110

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A restaurant will select select 1 card from a bowl to win a free lunch. Jimmy put in 10 cards in the bowl. The bowl has a total

amid [387]

If he put 10 in the bowl and there are 150 cards, the chance for him to win would be 10/150.
now by simplifying it, you get 1/15.
therefore answer is C

5 0

3 years ago

I need help with these three

Ludmilka [50]

A. The relationship of <7 and <8 are that they are vertical angles, and are congruent.

B. Since vertical angles are congruent, you can form an equation where the two measurements equal each other.

C. 5y-29=3y+19 then plug y into your equation: 5*24-29=91
2y=48 and so: <7 = 180-91=89 (and since <8 is congruent)
y=24 <8 also equals 89

Your second problem:
complementary are two angles that add up to 90 degrees.
<B=x, <A=2x
2x+x=90
3x=90
x=30 so: <B=30 degrees, <A=60 degrees

Your third problem:
1. Since A and B are parallel, angle 3x+7 and angle 4x+5 are same-sided exterior angles. That means that they both add up to 180 degrees. So if you should add the two and make it equal 180
2. 3x+7+4x+5=180
7x+12=180
7x=168
x=24
3. <6 is a corresponding angle with angle 3x+7, meaning that they are congruent. So plug x into 3x+7: 3*24+7=79 and since <6 is congruent to 3x+7, <6=79 degrees

6 0

3 years ago

Read 2 more answers

A genetic experiment involving peas yielded one sample of offspring consisting of 437437 green peas and 129129 yellow peas. Use

navik [9.2K]

Answer:

The null hypothesis: $\mathbf{H_o: p=0.27}$

The alternative hypothesis: $\mathbf{H_1: p \neq 0.27}$

Test statistics : z = −2.30

P-value: = 0.02144

Decision Rule: Since the p-value is lesser than the level of significance; then we reject the null hypothesis.

Conclusion: We accept the alternative hypothesis and conclude that under the same circumstances the proportion of offspring peas will be yellow is not equal to 0.27

Step-by-step explanation:

From the given information:

Let's state the null and the alternative hypothesis;

Since The claim is that 27% of the offspring peas will be yellow.

The null hypothesis state that the proportion of offspring peas will be yellow is equal to 0.27.

i.e

$\mathbf{H_o: p=0.27}$

The alternative hypothesis state that the proportion of offspring peas will be yellow is not equal to 0.27

$\mathbf{H_1: p \neq 0.27}$

The test statistics:

we are given 437 green peas and 129 yellow apples;

Hence;

$\hat p = \dfrac{x}{n}$

where ;

$\hat p$ = sample proportion

x = number of success

n = total number of the sample size

$\hat p = \dfrac{129}{437+129}$

$\hat p = \dfrac{129}{566}$

$\mathbf{\hat p = 0.2279}$

Now; the test statistics can be computed as :

$z = \dfrac { \hat p -p }{\sqrt {\dfrac{p(1-p)}{n} } }$

$z = \dfrac {0.2279 -0.27 }{\sqrt {\dfrac{0.27(1-0.27)}{566} } }$

$z = \dfrac {-0.043 }{\sqrt {\dfrac{0.27(0.73)}{566} } }$

$z = \dfrac {-0.043 }{\sqrt {\dfrac{0.1971}{566} } }$

$z = \dfrac {-0.043 }{\sqrt {3.48233216*10^{-4} } }$

$z = \dfrac {-0.043 }{0.01866} }$

z = −2.30

C. P-value

P-value = P(Z < z)

P-value = P(Z< -2.30)

By using the P-value method and the normal distribution as an approximation to the binomial distribution.

from the table of standard normal distribution

move left until the first column is reached. Note the value as –2.0

move upward until the top row is reached. Note the value as 0.30

find the probability value as 0.010724 by the intersection of the row and column values gives the area to the left of

z = -2.30

P- value = 2P(z ≤ -2.30)

P-value = 2 × 0.01072

P - value = 0.02144

Decision Rule: Since the p-value is lesser than the level of significance; then we reject the null hypothesis.

Conclusion: We accept the alternative hypothesis and conclude that under the same circumstances the proportion of offspring peas will be yellow is not equal to 0.27

8 0

2 years ago

The Candy Shack sells 138 pounds of candy on Tuesday. They sold 71.76 pounds of jelly beans. What percent of the candy sold was

Pepsi [2]

Answer:

<h2>52% were jelly beans!</h2>

Explanation:

Cross multiply the following:

$\frac{x}{100} = \frac{71.76}{138}$