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3 years ago

13

Natalie uses a 15% off coupon when she buys a camera. The original price of the camera is $45.00. How much money does Natalie sa

ve by using the coupon?

2 answers:

hram777 [196]3 years ago

5 0

Answer:

she saves 6.75 with the coupon

VARVARA [1.3K]3 years ago

5 0

45 x 15 = 675

675/100= 6.75

She saves $ 6.75

You might be interested in

Find the value of the missing variables.

dsp73

Answer:

$x^{\circ}=35^{\circ}\\ \\y^{\circ}=55^{\circ}$

Step-by-step explanation:

The measure of arc which the right triange cuts from the circle is $70^{\circ},$ this means the central angle has the same measure.

Angle with measure $x^{\circ}$ is inscribed angle subtended on the given arc. Its measure is half the measure of the central angle, hence

$x^{\circ}=\dfrac{1}{2}\cdot 70^{\circ}=35^{\circ}$

Angles with measures $x^{\circ}$ and $y^{\circ}$ are complementary angles (add up to 90°), so

$y^{\circ}=90^{\circ}-35^{\circ}=55^{\circ}$

6 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

PLEASE HURRY<br> which ordered pair represents point D

Varvara68 [4.7K]

(2,3) the order is rise over run so, go up two, and to the right 3 which gives you point D

3 0

3 years ago

Read 2 more answers

VLD [36.1K]

3x + 4(2) = 20
3x + 8 = 20
3x = 12
x = 4
(4,2)
You have y=2 then all you need to do is plug 2 into the y in the equation 3x + 4y = 20 and do the math to find x. Hope this helps

7 0

3 years ago

Which phrases below best describe the equation x - 240 = 91? (Select all)

nikdorinn [45]

Answer:

There isn't a specific answer in my knowledge but the answer that's matches with most of them is 149

5 0

2 years ago