My little sister don't think I'm right so I need help to prove her right

Sean answered 18 of 20 quiz questions correctly. What percent of the quiz questions did sean awnser correctly?

adell [148]

Answer:

90%

Step-by-step explanation:

18/20 × 100 = 90%

I hope this helps!

4 0

3 years ago

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Numerical coefficients of (I need dis quick would appreciate it)

Sonja [21]

Answer:

xy(5-6xy)/4

Step-by-step explanation:

Here, we want to evaluate the expression given

We have this as ;

(5xy - 6x^2y^2)/4

= xy(5-6xy)/4

6 0

3 years ago

consider the distribution of monthly social security (OASDI) payments. Assume a normal distribution with a standard deviation of

Orlov [11]

Answer:

$\mu = x - z(\sigma)$

$\mu = 1214.87 - 0.67(116) \\\\\mu = 1214.87 - 77.72 \\\\\mu = \$1137.15$

Therefore, the mean monthly payment is $1137.15.

Step-by-step explanation:

What is Normal Distribution?

We are given a Normal Distribution, which is a continuous probability distribution and is symmetrical around the mean. The shape of this distribution is like a bell curve and most of the data is clustered around the mean. The area under this bell shaped curve represents the probability.

We are asked to find the mean monthly social security (OASDI) payment.

Mean monthly payment = μ = ?

We are given that the standard deviation is $116

One-fourth of payments are above $1214.87

One-fourth means 25%

$P(X > x )= P(Z > z ) = 0.25\\\\P(X < x )= P(Z < z) = 1 - 0.25\\\\P(X < x )= P(Z < z) = 0.75\\\\$

From the z-table, the z-score corresponding to 0.75 is found to be 0.67

$z = 0.67$

The mean is found by

$x = \mu + z(\sigma)$

$\mu = x - z(\sigma)$

Where

x = $1214.87

z = 0.67

σ = $116

$\mu = 1214.87 - 0.67(116) \\\\\mu = 1214.87 - 77.72 \\\\\mu = \$1137.15$

Therefore, the mean monthly payment is $1137.15.

3 0

3 years ago

Point A is at (2,-8) and the point C is at (-4,7). Find the coordinates of point B on AC such that the ratio of AB to BC is 2:1.

pentagon [3]

Answer:

The coordinates of point B are (-2, 2)

Step-by-step explanation:

We have two points: A and C.

The coordinates for A are (2, -8) and the coordinates for C are (-4, 7).

We have to find the coordinates of the point B, that satisfies the condition that the distance AB is 2 times the distance BC.

We also know that B is a point of the line AC.

We can calculate the line AC as a linear function y=mx+b.

The slope m is:

$m=\dfrac{y_c-y_a}{x_c-x_a}=\dfrac{7-(-8)}{-4-2}=\dfrac{15}{-6}=-2.5$

Then, the y-intercept b can be calculated using the coordinates of one of the points, in this case point A:

$y=-2.5x+b\\\\b=y_a+2.5x_a=-8+2.5*2=-8+5=-3$

Then, we know that B is a point of the linear function y=-2.5x-3, within the range x ∈ (-4; 2).

To have a ratio AB to BC of 2 to 1, we can divide the length of the line AC in 3 parts, and the point B will be located in the end of the segment nearer to point C.

In the picture attached, you can see the division of the segment AC in three parts and the location of point B=(x, y).

Applying the Thales theorem, we can divide the segment in the y-axis in three and calculate y, and the same for the x-axis.

Then, the coordinate y for the point B is:

$y=y_c-(y_c-y_a)/3\\\\y=7-[7-(-8)]/3=7-15/3=7-5=2\\\\\\x=x_c-(x_c-x_a)/3\\\\x=-4-(-4-2)/3=-4-(-6)/3=-4+2=-2$

Then, the point B has coordinates (-2, 2).

We can verify the distances as:

$AB=\sqrt{(2-(-2))^2+((-8)-2)^2}=\sqrt{16+100}=\sqrt{116}\\\\\\BC=\sqrt{((-2)-(-4))^2+(2-7)^2}=\sqrt{4+25}=\sqrt{29}\\\\\\\dfrac{AB}{BC}=\dfrac{\sqrt{116}}{\sqrt{29}}=\sqrt{\dfrac{116}{29}}=\sqrt{4}=2$

4 0

3 years ago

Parker grew

vladimir1956 [14]

Answer:

63

Step-by-step explanation:

7 0

3 years ago

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