Sammy the turtle can walk 1/8 of a mile in an hour.How many hours will it take him to walk 1^1/4 miles?

Each of the following phrases describes a numerical value:

DanielleElmas [232]

Answer: C

Step-by-step explanation:

The answer is C

Step-by-step explanation:

C The opposite of 9 is the same distance from 0 on a number line as the absolute value of 9.

Absolute value is the distance from zero on a number line of and number positive or negative.

7 0

1 year ago

Read 2 more answers

Jeremy wants to give a 20% gratuity to his cab driver. His fare was $35.50. What is the total amount he will pay the driver?

velikii [3]

he will pay $42.60 to the driver :)

7 0

2 years ago

Read 2 more answers

Noor brought 212121 sheets of stickers. She gave \dfrac{1}{3} 3 1 start fraction, 1, divided by, 3, end fraction of a sheet to

My name is Ann [436]

Answer:

12 teachers will get 1/2 sheets each

Step-by-step explanation:

Noor bought 21 sheets of stickers

She gave 1/3 sheets to each 45 students

She wants to give teachers 1/2 of sheets

The question should be: how many teachers will she give

Total sheets=21

Students gets= 1/3 × 45

=45/3

=15 sheets

Remaining sheet= total sheets - students sheets

=21-15

=6 sheets

There are 6 sheets remaining for teachers

She wants to give 1/2 to each teacher

Then,

The number of teachers that will get =Remaining sheets ÷ each teacher's share

=6 ÷1/2

=6 × 2/1

=12 teachers

12 teachers will get 1/2 sheets each

5 0

1 year ago

It is believed that as many as 23% of adults over 50 never graduated from high school. We wish to see if this percentage is the

JulijaS [17]

Answer:

1) n=48

2) n=298

3) n=426

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".

$p$ represent the real population proportion of interest

$\hat p$ represent the estimated proportion for the sample

n is the sample size required (variable of interest)

$z$ represent the critical value for the margin of error

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

Part 1

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 90% of confidence, our significance level would be given by $\alpha=1-0.90=0.10$ and $\alpha/2 =0.05$ . And the critical value would be given by:

$z_{\alpha/2}=-1.64, z_{1-\alpha/2}=1.64$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.1$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can assume that the estimated proportion is 0.23 for the 25 to 30 group. And replacing into equation (b) the values from part a we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.1}{1.64})^2}=47.63$

And rounded up we have that n=48

Part 2

The margin of error on this case changes to 0.04 so if we use the same formula but changing the value for ME we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.04}{1.64})^2}=297.7$

And rounded up we have that n=298

Part 3

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And on this case we have that $ME =\pm 0.04$ and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}$ (b)

We can assume that the estimated proportion is 0.23 for the 25 to 30 group. And replacing into equation (b) the values from part a we got:

$n=\frac{0.23(1-0.23)}{(\frac{0.04}{1.96})^2}=425.22$

And rounded up we have that n=426

3 0

2 years ago

A machine is set to fill the small-size packages of m&m candies with 56 candies per bag. a sample revealed: three bags of 56

luda_lava [24]

In statistics, the amount of degrees of freedom is the quantity of values in the final computation of a statistic that are free to differ. In this case, you can get the answer by adding the number of bags and subtracting 1.

So in computation, this would look like: 3 + 2 + 1 + 2 - 1 = 7

Therefore, 7 is the degrees of freedom.

7 0

2 years ago