Help anyone need it asap<br> 8th grade math

Help me plz I need it I'm very desperate help

Klio2033 [76]

Answer:

1/45

Step-by-step explanation:

There are 10 marbles

P ( yellow) = yellow marbles / total = 2/10 = 1/5

We do not replace the marble

There are 9 marbles, 1 of which is yellow

P ( yellow) = yellow marbles / total = 1/9

P ( yellow, no replacement, yellow) = 1/5 * 1/9 = 1/45

8 0

3 years ago

Read 2 more answers

In a quality control test of parts manufactured at Dabco Corporation, an engineer sampled parts produced on the first, second, a

sammy [17]

Answer:

p value = 0.0174

Conclusion : we reject the null hypothesis

Step-by-step explanation:

Thinking step:

We need to perform a test to determine if the proportion of the good parts is the same for all three shifts at a significance level of $\alpha = 0.05$

Assumption : all the population for each or the three shifts is not equal.

Calculation:

Let p₁ be the sample of the first shift

p₂ be the sample of the second shift

p₃ be the sample of the third shift

According to the null hypothesis

H₀ = p₁ = p₂ = p₃

In other words, all the population sample proportions are equal.

Alternatively, we can assume that the three shift are not equal p₁ ≠ p₂ ≠ p₃

Tabulating and performing the $\chi$ ² test gives 8.10

degrees of freedom:

df = k - 1

= 3 - 1 = 2

Thus the degree of freedom is 2

Solving using the MINITAB software gives: p = 0.174

The solution shows that the p value < level of significance, then p-value lies in the range 0.0174≤ $\alpha$ ≤0.05

Therefore, we reject the null hypothesis based on the fact that the three shifts are not equal.

5 0

3 years ago

Braceleftzf y = 8/7 x − 2/3 <br> 8/3 x + y = 5/9

givi [52]

Answer:

(x, y) = (77/240, -3/10)

Step-by-step explanation:

It is convenient to write the equations in standard form.

Multiplying the first equation by 21 gives ...

21y = 24x -14

Multiplying the second equation by 8 gives ...

24x +9y = 5

Then the system of equations in standard form is ...

24x -21y = 14
24x +9y = 5

Subtracting the first from the second, we get ...

(24x +9y) -(24x -21y) = (5) -(14)

30y = -9

y = -9/30 = -3/10

Substituting this into the second equation, we have ...

24x +9(-3/10) = 5

24x = 7.7 . . . . . . . add 27/10

x = 7.7/24 = 77/240

The solution is (x, y) = (77/240, -3/10).

7 0

2 years ago

Two lines, A and B, are represented by the equations given below!

lara [203]

Answer:

The solutions to the system of equations are:

$y=-8,\:x=-4$

Thus, option C is true because the point satisfies BOTH equations.

Step-by-step explanation:

Given the system of the equations

$\begin{bmatrix}y=x-4\\ y=3x+4\end{bmatrix}$

Arrange equation variables for elimination

$\begin{bmatrix}y-x=-4\\ y-3x=4\end{bmatrix}$

$y-3x=4$

$-$

$\underline{y-x=-4}$

$-2x=8$

$\begin{bmatrix}y-x=-4\\ -2x=8\end{bmatrix}$

solve for x

$-2x=8$

Divide both sides by -2

$\frac{-2x}{-2}=\frac{8}{-2}$

$x=-4$

$\mathrm{For\:}y-x=-4\mathrm{\:plug\:in\:}x=-4$

$y-\left(-4\right)=-4$

$y+4=-4$

$y=-8$

The solutions to the system of equations are:

$y=-8,\:x=-4$

Thus, option C is true because the point satisfies BOTH equations.

8 0

3 years ago

A cyclist rides her bike at a rate of 15 miles per hour. What is this rate in kilometers per hour? How many kilometers will the

Trava [24]

Answer:

1. 24 km/hour

2. 48 km

Step-by-step explanation:

1 mile = 1.6 km

cyclist = 15 miles/ hour

we want to multiply speed by something that will cancel miles out and leave km. to do this, we want to multiply it by something with miles on the bottom and km on the top.

this is because

miles * km / miles = km as the miles cancel out and km is left in the numerator

thus,

1 mile = 1.6 km

divide both sides by 1.6 km to get 1 on a side

1 mile / 1.6 km = 1

alternatively, divide both sides by 1 mile to get 1 on a side

1.6 km / 1 mile = 1

since we want miles on the bottom, we choose the second option

cyclist = 15 miles / hour = 15 miles/hour * 1 = 15 miles/hour * 1.6km / 1 mile = 24 km /hour

24 km/hr for 2 hours = 24 km/hr * 2 hours = 24 * 2 km = 48 km

3 0

1 year ago

Help anyone need it asap 8th grade math