30% of your minutes are used up

A sample of students from an introductory psychology class were polled regarding the number of hours they spent studying for the

Anni [7]

Answer:

$8.68,13.16$

Step-by-step explanation:

Hint- First we have to calculate the mean and standard deviation of the sample and then applying formula for confidence interval we can get the values.

Mean of the sample is,

$\mu=\dfrac{\sum _{i=1}^{24}a_i}{24}=\dfrac{262}{24}=10.92$

Standard deviation of the sample is,

$\sigma =\sqrt{\dfrac{\sum _{i=1}^{24}\left(x_i-10.92\right)^2}{24-1}}=5.6$

The confidence interval will be,

$=\mu \pm Z\dfrac{\sigma}{\sqrt{n}}$

Here,

Z for 95% confidence interval is 1.96, and n is sample size which is 24.

Putting the values,

$=10.92 \pm 1.96\cdot \dfrac{5.6}{\sqrt{24}}$

$=10.92 \pm 2.24$

$=8.68,13.16$

Confidence interval is used to express the degree of uncertainty associated with a sample.

95% confidence interval means that if we used the same sampling method to select different samples and calculate an interval, we would expect the true population parameter to fall within the interval for 95% of the time.

5 0

3 years ago

Find the soluations to (x+3)^2=49

Jobisdone [24]

Answer:

x = 4 , − 10

Step-by-step explanation:

3 0

3 years ago

The measures of the legs of a right triangle are 15 m and 20 m. Use the triangle measures and substitute the lengths for a and b

DochEvi [55]

Answer:

25

Step-by-step explanation:

We can use the Pythagorean theorem to determine the length of the hypotenuse

a^2 + b^2 = c^2

15^2 + 20 ^2 = c^2

225 + 400 = c^2

625 = c^2

Take the square root of each side

sqrt(625) = sqrt(c^2)

25 = c

5 0

3 years ago

A cylinder and a cone have the same volume. The cylinder has radius x and height y. The cone has radius 1/3x. Find the height of

Temka [501]

Great question! I had this question in Geometry on Edmentum.

Answer: Height of cone = 3y

Step-by-step explanation:

We know that the cylinder and the cone have the same volume. The cylinder has radius x and height y. We will make use of the formulas:

Volume of cylinder = πr²h

Volume of cone = 1/3πr²h

Since the cone has radius 1/3x, we will have to make its height 3 times of y (the height of the cylinder) to make both the cylinder and the cone have the same volume.

So, the height of the cone is equal to 3y.

Hope this helps, and have a wonderful day! :D

Please mark me brainliest! I don't have trouble getting points, but I do when it comes to brainliest.

7 0

3 years ago

HELP! 8TH GRADE MATH PLS LOL

LekaFEV [45]

<h2><u>Given</u><u>:</u><u>-</u></h2>

${ \large{➢ \: \: \bf{x = - 8}}}$