A survey of cars on a certain stretch of highway during morning commute hours showed that 70% had only one occupant, 15% had 2, 10% had 3, 3% had 4, and 2% had 5. Let Xrepresent the number of occupants in a randomly chosen car.a. Find the probability mass function of X.

b. Find P(X ≤ 2).

c. Find P(X > 3).

d. Find μX.

e. Find σX

Answers

Answer 1
Answer:

Answer:

a) X    1       2      3       4       5

P(X) 0.7  0.15  0.10  0.03  0.02

b) P(X \leq 2) = P(X=1) +P(X=2) = 0.7+0.15=0.85

c) P(X >3) = 1-P(X \leq 3) = 1-[P(X=1) +P(X=2)+P(X=3)]=1-[0.7+0.15+0.1]= 0.05

d) E(X) = \sum_(i=1)^n X_i P(X_i) = 1*0.7 +2*0.15+ 3*0.1+4*0.03+ 5*0.02= 1.52

e) E(X^2) = \sum_(i=1)^n X^2_i P(X_i) = 1*0.7 +4*0.15+ 9*0.1+16*0.03+ 25*0.02=3.18

Var(X) = E(X^2) -[E(X)]^2= 3.18- (1.52)^2 = 0.8996

\sigma= √(Var(X))= √(0.8996)= 0.933

Step-by-step explanation:

Part a

From the information given we define the probability distribution like this:

X       1       2      3       4       5

P(X) 0.7  0.15  0.10  0.03  0.02

And we see that the sum of the probabilities is 1 so then we have a probability distribution

Part b

We want to find this probability:

P(X \leq 2) = P(X=1) +P(X=2) = 0.7+0.15=0.85

Part c

We want to find this probability P(X>3)

And for this case we can use the complement rule and we got:

P(X >3) = 1-P(X \leq 3) = 1-[P(X=1) +P(X=2)+P(X=3)]=1-[0.7+0.15+0.1]= 0.05

Part d

We can find the expected value with this formula:

E(X) = \sum_(i=1)^n X_i P(X_i) = 1*0.7 +2*0.15+ 3*0.1+4*0.03+ 5*0.02= 1.52

Part e

For this case we need to find first the second moment given by:

E(X^2) = \sum_(i=1)^n X^2_i P(X_i) = 1*0.7 +4*0.15+ 9*0.1+16*0.03+ 25*0.02=3.18

And we can find the variance with the following formula:

Var(X) = E(X^2) -[E(X)]^2= 3.18- (1.52)^2 = 0.8996

And we can find the deviation taking the square root of the variance:

\sigma= √(Var(X))= √(0.8996)= 0.933


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The area of the circle is 379.94 square inches.

What is area of a circle?

The area of a circle is the space occupied by the circle in a two-dimensional plane. Alternatively, the space occupied within the boundary/circumference of a circle is called the area of the circle. The formula for the area of a circle is A = πr², where r is the radius of the circle.

Given that, the area of a circle with a radius of 11 inches.

Here, area of a circle is

A=3.14×11²

= 3.14×121

= 379.94 square inches

Therefore, the area of the circle is 379.94 square inches.

Learn more about the area of a circle here:

brainly.com/question/28642423.

#SPJ5

Answer:

A = 379.94 square inches

Step-by-step explanation:

The area of a circle equation is:

A = pi *  r^2

Fill in what you know and solve:

A = 3.14 * 11^2

A = 3.14 * 121

A = 379.94

In a certain soccer tournament you play 6 games. In every match you get 3 points if you win, 1 point for a draw and 0 points if you lose. For each match the probability you win is 0.5, the probability you draw is 0.1 and the probability you lose is 0.4, independently of the results of all other matches. What is the probability you Önish?

Answers

Answer:

0.430625 = 0.431

Step-by-step explanation:

Let W represent winning, D represent a draw and L represent a loss.

12+ points can be garnered in each of the following ways.

6W 0D 0L

5W 1D 0L

5W 0D 1L

4W 2D 0L

4W 1D 1L

4W 0D 2L

3W 3D 0L

The probability of getting 12+ points is the sum of all these 7 probabilities.

Knowing that P(W) = 0.5

P(D) = 0.1

P(L) = 0.4

P(6W 0D 0L) = [6!/(6!0!0!)] 0.5⁶ 0.1⁰ 0.4⁰ = 0.015625

P(5W 1D 0L) = [6!/(5!1!0!)] 0.5⁵ 0.1¹ 0.4⁰ = 0.01875

P(5W 0D 1L) = [6!/(5!0!1!)] 0.5⁵ 0.1⁰ 0.4¹ = 0.075

P(4W 2D 0L) = [6!/(4!2!0!)] 0.5⁴ 0.1² 0.4⁰ = 0.09375

P(4W 1D 1L) = [6!/(4!1!1!)] 0.5⁴ 0.1¹ 0.4¹ = 0.075

P(4W 0D 2L) = [6!/(4!0!2!)] 0.5⁴ 0.1⁰ 0.4² = 0.15

P(3W 3D 0L) = [6!/(3!3!0!)] 0.5³ 0.1³ 0.4⁰ = 0.0025

The probability of getting 12+ points = 0.015625 + 0.01875 + 0.075 + 0.09375 + 0.075 + 0.15 + 0.0025 = 0.430625

The sum of three consecutive integers is 267. What is the largest integer?

Answers

Answer:

let integers be x,2x, 3x respectively

x+2x+3x= 267

6x= 267

x=267/6= 44.5

2x= 44.5*2= 89

3x= 44.5*3= 133.5

largest integer = 133.5

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Answers

Answer:

The imaginary part is:  z = 19

Step-by-step explanation:

For real numbers a and b, a number written in form a+bi is called a acomplex number. The value a is called the real part and b is called the imaginary part of complex number.

Ashley has an action figure collection of 500 action figures. She keeps 430 of the action figures on her wall. What percentage of Ashley's action figure collection does she keep on her wall?

Answers

Answer: 86%

Step-by-step explanation:

430/500=0.86

0.86x100= 86

86%

Answer:

86%

Step-by-step explanation:

F (x) = 2x^2 - 4x + 1​

Answers

i don't know specifically what you are looking for but:

Direction: Opens Up

Vertex: (1, -1)

Axis of Symmetry: x = 1

and i attached the graph

Answer:  x = √(((-F - 4)^2)/16 - 1/2) + (F + 4)/4 or x = (F + 4)/4 - √(((-F - 4)^2)/16 - 1/2)

Step-by-step explanation:

Solve for x:

F x = 2 x^2 - 4 x + 1

Subtract 2 x^2 - 4 x + 1 from both sides:

-2 x^2 + F x + 4 x - 1 = 0

Collect in terms of x:

-1 + x (F + 4) - 2 x^2 = 0

Divide both sides by -2:

1/2 + 1/2 x (-F - 4) + x^2 = 0

Subtract 1/2 from both sides:

1/2 x (-F - 4) + x^2 = -1/2

Add 1/16 (-F - 4)^2 to both sides:

1/16 (-F - 4)^2 + 1/2 x (-F - 4) + x^2 = 1/16 (-F - 4)^2 - 1/2

Write the left hand side as a square:

(1/4 (-F - 4) + x)^2 = 1/16 (-F - 4)^2 - 1/2

Take the square root of both sides:

1/4 (-F - 4) + x = √(1/16 (-F - 4)^2 - 1/2) or 1/4 (-F - 4) + x = -√(1/16 (-F - 4)^2 - 1/2)

Subtract 1/4 (-F - 4) from both sides:

x = √(((-F - 4)^2)/16 - 1/2) + (F + 4)/4 or 1/4 (-F - 4) + x = -√(1/16 (-F - 4)^2 - 1/2)

Subtract 1/4 (-F - 4) from both sides:

Answer: x = √(((-F - 4)^2)/16 - 1/2) + (F + 4)/4 or x = (F + 4)/4 - √(((-F - 4)^2)/16 - 1/2)