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3 years ago

What is the volume of the cube?

Mathematics

2 answers:

RideAnS [48]3 years ago

8 0

Volume=side³
side=2 in

Volume=(2 in)³=8 in³

answer: B 8 cubic inches.

MrMuchimi3 years ago

5 0

Volume = side * side * side

Volume = 2 in * 2 in * 2in

Volume = 8 in^3

Volume = 8 cubic inches

The answer is B.

You might be interested in

Examine the required sample size needed to be able to

Xelga [282]

Answer:

$n=(\frac{2.33(500)}{10})^2 =13572.25 \approx 13573$

And if we use a sample level of n =2000 the margin of error would be higher as we can see here:

$ME=2.33\frac{500}{\sqrt{2000}}=26.05$

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=500$ represent the population standard deviation assumed

n represent the sample size (variable of interest)

Confidence =98% or 0.98

ME = 10 represent the margin of error desired

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (a)

And on this case we have that ME =10 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

The critical value for 98% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.01;0;1)", and we got $z_{\alpha/2}=2.33$ , replacing into formula (b) we got:

$n=(\frac{2.33(500)}{10})^2 =13572.25 \approx 13573$

So the answer for this case would be n=13573 rounded up to the nearest integer

And if we use a sample level of n =2000 the margin of error would be higher as we can see here:

$ME=2.33\frac{500}{\sqrt{2000}}=26.05$

3 0

4 years ago

Use any method to solve the equation. If necessary, round to the nearest hundredth. 9x^2-21=0

zavuch27 [327]

Answer:

x = 1.53, -1.53.

Step-by-step explanation:

9x^2 - 21 = 0

9x^2 = 21

x^2 = 21/9

x = +/- √21 / 3

x = 1.53, -1.53.

7 0

3 years ago

Diego bought 12 mini muffins for $4.20.<br> How many mini muffins could Diego buy with $3.00?

Vesnalui [34]

Answer:

Step-by-step explanation:

First divide 12 into 4.20 = 35

They are .35 cents a piece. Dive .35 by 3.00 dollars. You get approx 8.5 muffins.

7 0

3 years ago

The life times of light bulbs produced by a particular manufacturer have a mean of 1,200 hours and a standard deviation of 400 h

Nezavi [6.7K]

Answer:

a. 1200hours

b. σ² = 400² =160000hour

c. standard error = 133.33

d. for 9 lightbulb it is likely that 9*0.146 = 1.31 bulbs will have lives of fewer than 1,050 hours?

Step-by-step explanation:

mean of 1,200 hours

σ, a standard deviation of 400 hours.

Sample size, N = nine bulbs,

a) mean of the sample mean lifetime: is given as 1,200 hours

b) variance of the sample mean is the square of the σ, a standard deviation of 400 hours.

σ² = 400² =160000hours

c) What is the standard error of the sample mean?

The standard deviation of a sampling distribution of mean values is called the standard error of the means,

standard error of the means, σx = σ √N

The formula for the standard error of the means is true for all values infinite number of sample, N.

σx = σ √N

=400 √9 = 400/3 =133.3333

d) the probability that, on average, those nine lightbulbs have lives of fewer than 1,050 hours

The area under part of a normal probability curve is directly proportional to probability and the value is calculated as

z = ( x₁−x) /σ

where z = propability of normal curve

x₁ = variate mean = 1050hours

x = mean of 1200hours

σ = standard deviation = 400

applying the formula,

z= (1050-1200)/400

z = 150/400 =0.375

Using a table of partial areas beneath the standardized normal curve (see Table of normal curve, a z-value of 0.375 corresponds to an area of 0.1460 between the mean value.

Thus the probability of a lightbulbs having lives of fewer than 1,050 hours is 0.1460.

for 9 lightbulb it is likely that 9*0.146 i.e. 1.31 bulbs will have lives of fewer than 1,050 hours?

8 0

3 years ago

A psychologist collects data on the time, w, in minutes, people walk each day and their scores, t ,on a stress test. The scores

Svetach [21]

The answer is the last one D that is the correct answer
good lock!!!

7 0

3 years ago