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3 years ago

Explain the error in the work shown. Find the correct answer.

Mathematics

2 answers:

const2013 [10]3 years ago

5 0

You cant have a negative exponent

Kobotan [32]3 years ago

4 0

The mistake is in 3rd step, as we can't equate powers if bases are different.
4^-3=2^8a
2^-6=2^8a
-6=8a
-3/4=a

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Health insurers are beginning to offer telemedicine services online that replace the common office visit. A company provides a v

Veronika [31]

Answer:

$\text {CI} = (60.54, \: 81.46)\\\\$

Therefore, we are 95% confident that actual mean savings for a televisit to the doctor is within the interval of ($60.54 to $81.46)

Step-by-step explanation:

Let us find out the mean savings for a televisit to the doctor from the given data.

Using Excel,

=AVERAGE(number1, number2,....)

The mean is found to be

$\bar{x} = \$71$

Let us find out the standard deviation of savings for a televisit to the doctor from the given data.

Using Excel,

=STDEV(number1, number2,....)

The standard deviation is found to be

$s = \$ 22.35$

The confidence interval is given by

$\text {confidence interval} = \bar{x} \pm MoE\\\\$

Where the margin of error is given by

$$ MoE = t_{\alpha/2}(\frac{s}{\sqrt{n} } ) $ \\\\$

Where n is the sample of 20 online doctor visits, s is the sample standard deviation and $t_{\alpha/2}$ is the t-score corresponding to a 95% confidence level.

The t-score is given by is

Significance level = α = 1 - 0.95 = 0.05/2 = 0.025

Degree of freedom = n - 1 = 20 - 1 = 19

From the t-table at α = 0.025 and DoF = 19

t-score = 2.093

So, the margin of error is

$MoE = t_{\alpha/2}(\frac{s}{\sqrt{n} } ) \\\\MoE = 2.093\cdot \frac{22.35}{\sqrt{20} } \\\\MoE = 2.093\cdot 4.997\\\\MoE = 10.46\\\\$

So the required 95% confidence interval is

$\text {CI} = \bar{x} \pm MoE\\\\\text {CI} = 71 \pm 10.46\\\\\text {CI} = 71 - 10.46, \: 71 + 10.46\\\\\text {CI} = (60.54, \: 81.46)\\\\$

Therefore, we are 95% confident that actual mean savings for a televisit to the doctor is within the interval of ($60.54 to $81.46)

7 0

3 years ago

If f(x) equals x/2+8 what is f(x) when x=10

Sphinxa [80]

Answer:

Step-by-step explanation:

Since we want to find f(x) when x equals 10, we can substitute 10 in for x

f(x)=x/2 +8

f(10)=10/2+8

Divide 10 by 2

f(10)=5+8

Add 5 and 8

f(10)=13

So, f(x) when x=10 is 13

4 0

3 years ago

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Suppose you ride your bicycle into the countryside on a bike path. You travel 6 km the first hour, 3 km

Ksivusya [100]

Answer:

25km/h

Step-by-step explanation:

6 0

3 years ago

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A taxi company charges $2.25 per ride plus $0.30 per mile. Enter a linear model represents the cost, C, as a function of d, the

Anna007 [38]

Answer:

C(d) = d(2.25) + m(0.3)

Step-by-step explanation:

A taxi company charges $2.25 per ride plus $0.30 per mile.

Let d represent number of rides..

Let m represent number of Miles...

Then let C represent the total cost for each ride at a specific number of Miles.

The linear model representing the cost as a function of d the total ride

C(d) = d(2.25) + m(0.3)

The values stand independently because the customer can choose a different right and a different mile.

7 0

3 years ago

Write the number 0.5 in the form mc003-1.jpg, using integers, to show that it is a rational number.

Tasya [4]

If $x=0.5$ , then $10x=5$ , and so $x=\dfrac5{10}=\dfrac5{5\times2}=\dfrac12$ .

6 0

3 years ago