99 POINT PROJECT -- ACTUALLY DO IT, DONT TELL ME HOW! 99 POINTS.

Let X represent the time it takes from when someone enters the line for a roller coaster until they exit on the other side. Cons

Yuri [45]

Answer:

a. E(x) = 3.730

b. c = 3.8475

c. 0.4308

Step-by-step explanation:

a.

Given

0 x < 3

F(x) = (x-3)/1.13, 3 < x < 4.13

1 x > 4.13

Calculating E(x)

First, we'll calculate the pdf, f(x).

f(x) is the derivative of F(x)

So, if F(x) = (x-3)/1.13

f(x) = F'(x) = 1/1.13, 3 < x < 4.13

E(x) is the integral of xf(x)

xf(x) = x * 1/1.3 = x/1.3

Integrating x/1.3

E(x) = x²/(2*1.13)

E(x) = x²/2.26 , 3 < x < 4.13

E(x) = (4.13²-3²)/2.16

E(x) = 3.730046296296296

E(x) = 3.730 (approximated)

b.

What is the value c such that P(X < c) = 0.75

First, we'll solve F(c)

F(c) = P(x<c)

F(c) = (c-3)/1.13= 0.75

c - 3 = 1.13 * 0.75

c - 3 = 0.8475

c = 3 + 0.8475

c = 3.8475

c.

What is the probability that X falls within 0.28 minutes of its mean?

Here we'll solve for

P(3.73 - 0.28 < X < 3.73 + 0.28)

= F(3.73 + 0.28) - F(3.73 + 0.28)

= 2*0.28/1.3 = 0.430769

= 0.4308 -- Approximated

5 0

3 years ago

You throw a ball up and its height h can be tracked using the equation h=2x^2-12x+20.

postnew [5]

This problem seems to be wrong because no minimum point was found and no point of landing exists

Answer:

1) There is no maximum height

2) The ball will never land

Step-by-step explanation:

Derivatives

Sometimes we need to find the maximum or minimum value of a function in a given interval. The derivative is a very handy tool for this task. We only have to compute the first derivative f' and have it equal to 0. That will give us the critical points.

Then, compute the second derivative f'' and evaluate the critical points in there. The criteria establish that

If f''(a) is positive, then x=a is a minimum

If f''(a) is negative, then x=a is a maximum

1)

The function provided in the question is

$h(x)=2x^2-12x+20$

Let's find the first derivative

$h'(x)=4x-12$

solving h'=0:

$4x-12=0$

x=3

Computing h''

h''(x)=4

It means that no matter the value of x, the second derivative is always positive, so x=3 is a minimum. The function doesn't have a local maximum or the ball will never reach a maximum height

2)

To find when will the ball land, we set h=0

$2x^2-12x+20=0$

Simplifying by 2

$x^2-6x+10=0$

Completing squares

$x^2-6x+9+10-9=0$

Factoring and rearranging

$(x-3)^2=-1$

There is no real value of x to solve the above equation, so the ball will never land.

This problem seems to be wrong because no minimum point was found and no point of landing exists

3 0

3 years ago

2. The water level in a reservoir is now 52 meters. Which equation can be used to find the initial depth, d, if this is the wate

Maru [420]

Answer:

1.23d = 52

Explanation:

If 52 meters is the water level after a 23% increase, then we can say that the initial depth d added to the 23% of d is equal to 52 meters. So:

d + 23%d = 52 meters

Since 23% is equivalent to 0.23, we get:

d + 0.23d = 52

Finally, adding the like terms, we get:

(1 + 0.23)d = 52

1.23d = 52

So, the equation is:

1.23d = 52

8 0

1 year ago

Round your answer to the nearest tenth.

Kruka [31]

Answer:

The value of MB = 8.4

Step-by-step explanation:

We know that the point of intersection of the Medians of a triangle is called the centroid of a triangle.

Thus,

For the given triangle ΔJKL,

The point M is the centroid of the triangle.

We also know that the centroid is 2/3 of the distance from each vertex to the midpoint of the opposite side.

Also, each Median is split into two parts such that the longer part is 2 times the length of the smaller part.

In our case,

The median KB is split into two parts such that the longer part KM is 2 times the length of the smaller part MB.

i.e.

KM = 2 MB

Given KM = 16.8

so substitute KM = 16.8 in the equation KM = 2 MB

16.8 = 2 MB

MB = 16.8/2

MB = 8.4

Therefore, the value of MB = 8.4

7 0

3 years ago

Read 2 more answers

Stuck on this answer have no clue?!

vredina [299]

I think your answer is correct!

6 0

3 years ago