What is y=4,000-400 simplify to

If a figure is a trapezoid, in what other way or ways can you classify it?

You can classify it by saying it's a Polygon

4 0

3 years ago

Which of the following SRS designs will give the most precision (smallest standard error) for estimating a population mean? Assu

Serjik [45]

Answer:

Design 3: An SRS of size 3000 from a population of size 300,000,000

Step-by-step explanation:

To check the SRS designs will give the most precision (smallest standard error) for estimating a population mean, we'll make use of the following formula:

V(y) = S²/n( 1 - n/N)

Where S² is a constant for the three SRS designs

Check the first design

n = 400

N = 4000

So, V(y) = S²/400 (1 - 400/4000)

V(y) = S²/400(1 - 0.1)

V(y) = 0.0025S²(0.9)

V(y) = 0.00225S²

V(y) = 2.25S²E-3

The second design

n = 30

N = 300

So, V(y) = S²/30 (1 - 30/300)

V(y) = S²/30(1 - 0.1)

V(y) = S²/30(0.9)

V(y) = 0.03S²

V(y) = 3S²E-2

The third design

n = 3,000

N = 300,000,000

So, V(y) = S²/3,000 (1 - 3,000/300,000,000)

V(y) = S²/3,000(1 - 0.00001)

V(y) = S²/3,000(0.99999)

V(y) = 0.00033333

V(y) = 3.33S²E-4

7 0

3 years ago

A large university accepts 60% of the students who apply. Of the students the university accepts, 25% actually enroll. If 10,000

Alja [10]

Answer:

1500 students

Step-by-step explanation:

To do this you must figure how many people the university accepts by times the no. of students applying by the percentage that are accepted

10,000 X 60% = 6000 students

You then figure out the number of students that actually enrols by doing

no. of students accepted X 25%

6000 X 25% = 1500 students

6 0

3 years ago

Help me please I really do need help tho

Mekhanik [1.2K]

Answer: What musickp8809 said

Step-by-step explanation: Give him brainliest, bc that's what i want for christmas.

6 0

3 years ago

A small rocket is fired from a launch pad 10 m above the ground with an initial velocity left angle 250 comma 450 comma 500 righ

jonny [76]

Let $\vec r(t),\vec v(t),\vec a(t)$ denote the rocket's position, velocity, and acceleration vectors at time $t$ .

We're given its initial position

$\vec r(0)=\langle0,0,10\rangle\,\mathrm m$

and velocity

$\vec v(0)=\langle250,450,500\rangle\dfrac{\rm m}{\rm s}$

Immediately after launch, the rocket is subject to gravity, so its acceleration is

$\vec a(t)=\langle0,2.5,-g\rangle\dfrac{\rm m}{\mathrm s^2}$

where $g=9.8\frac{\rm m}{\mathrm s^2}$ .

a. We can obtain the velocity and position vectors by respectively integrating the acceleration and velocity functions. By the fundamental theorem of calculus,

$\vec v(t)=\left(\vec v(0)+\displaystyle\int_0^t\vec a(u)\,\mathrm du\right)\dfrac{\rm m}{\rm s}$

$\vec v(t)=\left(\langle250,450,500\rangle+\langle0,2.5u,-gu\rangle\bigg|_0^t\right)\dfrac{\rm m}{\rm s}$

(the integral of 0 is a constant, but it ultimately doesn't matter in this case)

$\boxed{\vec v(t)=\langle250,450+2.5t,500-gt\rangle\dfrac{\rm m}{\rm s}}$

and

$\vec r(t)=\left(\vec r(0)+\displaystyle\int_0^t\vec v(u)\,\mathrm du\right)\,\rm m$

$\vec r(t)=\left(\langle0,0,10\rangle+\left\langle250u,450u+1.25u^2,500u-\dfrac g2u^2\right\rangle\bigg|_0^t\right)\,\rm m$

$\boxed{\vec r(t)=\left\langle250t,450t+1.25t^2,10+500t-\dfrac g2t^2\right\rangle\,\rm m}$

b. The rocket stays in the air for as long as it takes until $z=0$ , where $z$ is the $z$ -component of the position vector.

$10+500t-\dfrac g2t^2=0\implies t\approx102\,\rm s$

The range of the rocket is the distance between the rocket's final position and the origin (0, 0, 0):

$\boxed{\|\vec r(102\,\mathrm s)\|\approx64,233\,\rm m}$

c. The rocket reaches its maximum height when its vertical velocity (the $z$ -component) is 0, at which point we have

$-\left(500\dfrac{\rm m}{\rm s}\right)^2=-2g(z_{\rm max}-10\,\mathrm m)$

$\implies\boxed{z_{\rm max}=125,010\,\rm m}$

7 0

3 years ago