Bored someone talk to me

n a study of cell phone use and brain hemispheric dominance, an Internet survey was e-mailed to 2472 subjects randomly selecte

Leona [35]

Answer:

0.3876<p<0.4389

Step-by-step explanation:

-Given $n=2472, \ x=1022 , \ CI=0.99$

-We calculate the proportion of surveys returned:

$\hat p=\frac{1022}{2472}\\\\=0.4134$

For a 99% confidence interval:

$z_{\alpha/2}=2.576$

#The margin of error is calculated as;

$ME=z_{0.005}\times \sqrt{\frac{\hat p(1-\hat p)}{n}}\\\\=2.576\times \sqrt{\frac{0.4134(1-0.4134)}{2472}}\\\\=0.0255$

The confidence interval are then:

$CI=\hat p\pm ME\\\\=0.4134\pm 0.0255\\\\=[0.3876,0.4389]$

Hence, the confidence interval is 0.3876<p<0.4389

5 0

3 years ago

Mr. Jackman gives $32.00 to his four children to share equally. How much will each of his children get?

maksim [4K]

Answer:

$8.00 per child

Step-by-step explanation:

Mr. Jackman= $32

Children= 4

per child= $32/4

$8.00

7 0

2 years ago

At time t = 0 a car has a velocity of 16 m/s. It slows down with an acceleration given by –0.50t, in m/s^2 for t in seconds. By

anygoal [31]

The car's velocity at time $t$ is

$v(t)=16\dfrac{\rm m}{\rm s}+\displaystyle\int_0^t\left(\left(-0.50\frac{\rm m}{\mathrm s^2}\right)u\right)\,\mathrm du=16\dfrac{\rm m}{\rm s}+\left(-0.25\dfrac{\rm m}{\mathrm s^2}\right)t^2$

It comes to rest at

$v(t)=0\implies16\dfrac{\rm m}{\rm s}=\left(0.25\dfrac{\rm m}{\mathrm s^2}\right)t^2\implies t=8.0\,\mathrm s$

Its velocity over this period is positive, so that the total distance the car travels is

$\displaystyle\int_0^{8.0}v(t)\,\mathrm dt=\left(16\dfrac{\rm m}{\rm s}\right)(8.0\,\mathrm s)+\frac13\left(-0.25\dfrac{\rm m}{\mathrm s^2}\right)(8.0\,\mathrm s)^3=\boxed{85\,\mathrm m}$

so the answer is D.

4 0

2 years ago

Courtney constructed this figure using a compass with its width set equal to PR, the radius of the circle. She claims triangle P

murzikaleks [220]

Answer:

B

Step-by-step explanation:

It helps if you have the figure included. However, since it is not, we can assume that she has gone around the circle with all six sides of the hexagon is set to PR.

That makes the hexagon with 6 equal sides. It also makes each triangle using one of the sides equal to PR. The radii are all equal. There are 6 triangles making up the hexagon.

Both statements she makes are true and that makes B the answer.

6 0

3 years ago

HELP! I'm unsure of what this question is actually asking. I solved for side YZ, and found it to be 27.04 m. Is it asking for th

Arada [10]

The boy scout was walking on trail YZ from point Y to Z.
Then he decided to go to trail YX. He could have gone back to point Y, made a 90-deg turn and start walking along trail YX. He did not do that.

To go from trail YZ to trail YX, when he got to point Z, he made a 47-deg right turn onto segment XZ which is the short curt between trails YZ and YX.
He walked along ZX until he got onto trail YX at point X. Point X is 29 meters from point Y.

The figure shows angle theta as the 47-degree turn he made.

He walked along the shortcut ZX. When he got to point X, he was on trail YX. The point he got onto trail YX is point X and it is 29 m from point Y.

The question is what is the distance of the shortcut, XZ?

You have a right triangle, XYZ, with legs YX and YZ, and with hypotenuse XZ. You are given one of the acute angles as 47 deg. You are looking for the length of the hypotenuse, XZ.

For the given angle theta, XY is the opposite leg.
XZ is the hypotenuse of the triangle.

The trig ratio that relates the opposite leg to the hypotenuse is the sine.

$\sin \theta = \dfrac{opp}{hyp}$

$\sin 47^\circ = \dfrac{29~m}{XZ}$

$XZ \sin 47^\circ = 29~m$

$XZ = \dfrac{29~m}{\sin 47^\circ}$

$XZ = 39.7~m$

3 0

2 years ago