Is this a Function? A. Yes B.No C. Maybe D. Other

Mabel is comparing the prices of two car rental companies. Company A charges $35 per day and an additional $15 as service charge

patriot [66]

Company A : C = 35D + 15....C is total cost and D is number of days
company B : C = 42D + 10...C is total cost and D is number of days
================
which company charges less for renting for 6 days
company A :
C = 35(6) + 15 = 225

company B :
C = 42(6) + 10 = 262

so company A charges less when renting for 6 days
=================
for 10 days...
company A :
C = 35(10) + 15 = 365

company B :
C = 42(10) + 10 = 430

so there would be (430 - 365) = 65 saved when using company A instead of company B

4 0

3 years ago

In a random sample of 80 teenagers, the average number of texts handled in a day is 50. The 96% confidence interval for the mean

Nastasia [14]

Answer:

a) $\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

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

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

b) $ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

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

$\mu$ population mean (variable of interest)

$\sigma$ represent the population standard deviation

n=80 represent the sample size

Solution to the problem

Part a

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

For this case we can calculate the mean like this:

$\bar X =\frac{46+54}{2}=50$

And the margin of error is given by:

$ME= \frac{54-46}{2}= 4$

The confidence level is 0.96 and the significance level is $\alpha=1-0.96=0.04$ and the value of $\alpha/2 =0.02$ and the margin of error is given by:

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

We can calculate the critical value and we got:

$z_{\alpha/2} = 2.05$

And if we solve for the deviation like this:

$\sigma = ME * \frac{\sqrt{n}}{z_{\alpha/2}}$

And replacing we got:

$\sigma =4 *\frac{\sqrt{80}}{2.05} =17.45$

Part b

For this case is the sample size is doubled the margin of error would be:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}=2.05 *\frac{17.45}{\sqrt{160}}=2.828$

And as we can see that the margin of error would be lower than the original value of 4, the margin of error would be reduced by a factor $\sqrt{2}$

5 0

3 years ago

Round 82.265 to the nearest whole number

poizon [28]

$82.265\approx82$

5 0

3 years ago

Laurie buys four bags of candy with 10 pieces of candy in each bag. Her father then gives her 5 more pieces of candy. Laurie wan

Alborosie

Your Question:
Laurie buys four bags of candy with 10 pieces of candy in each bag. Her father then gives her 5 more pieces of candy. Laurie wants to give as much of her candy as she can to each of her six friends, and she wants to make sure they each get an equal number of pieces. How many pieces will be left over, if any, after Laurie gives her friends the candy?
My Answer:
If Laurie has four bags with ten pieces in each bag, and if her father gives her five more pieces, she would have forty-five pieces and if she has six friends and wants to share it equally with six friends. Each friend would get 7 pieces.
My Work:
45 ÷ 6 = 7.5
Hope I helped
♥ James.

7 0

3 years ago

Read 2 more answers

A TV has a listed price of $885.98 before tax. If the sales tax rate is 8.5%, find the total cost of the TV with sales tax

Butoxors [25]

Answer:

net amount $885.98 tax at 8.5% is $75.31 gross amount is $961.29

8 0

3 years ago