Food prices including tax

Westkost [7]

F(x) = x^2 - 8x + 5

f(-1) = -1^2 - 8(-1) + 5
f(-1) = 1 + 8 + 5
f(-1) = 14 <==

3 0

3 years ago

Suppose that at a state college, a random sample of 41 students is drawn, and each of the 41 students in the sample is asked to

ra1l [238]

Answer:

The confidence interval for 90% confidence would be narrower than the 95% confidence

Step-by-step explanation:

From the question we are told that

The sample size is n = 41

For a 95% confidence the level of significance is $\alpha = [100 - 95]\% = 0.05$ and

the critical value of $\frac{\alpha }{2}$ is $Z_{\frac{\alpha }{2} } =Z_{\frac{0.05 }{2} }= 1.96$

For a 90% confidence the level of significance is $\alpha = [100 - 90]\% = 0.10$ and

the critical value of $\frac{\alpha }{2}$ is $Z_{\frac{\alpha }{2} } =Z_{\frac{0.10 }{2} }= 1.645$

So we see with decreasing confidence level the critical value decrease

Now the margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} } * \frac{s}{\sqrt{n} }$

given that other values are constant and only $Z_{\frac{\alpha }{2} }$ is varying we have that

$E\ \ \alpha \ \ Z_{\frac{\alpha }{2} }$

Hence for reducing confidence level the margin of error will be reducing

The confidence interval is mathematically represented as

$\= x - E < \mu < \= x + E$

Now looking at the above formula and information that we have deduced so far we can infer that as the confidence level reduces , the critical value reduces, the margin of error reduces and the confidence interval becomes narrower

3 0

3 years ago

5x6 = (_X 6) + (2x_)

kati45 [8]

Answer:

Step-by-step explanation:

6 0

3 years ago

5. Carla babysits and tutors to make extra money. She babysits for $5 an hour and tutors for $10 an hour.

HACTEHA [7]

Carla can babysit for 5 hours and tutor for 7 hours or babysit for 8 hours and tutor for 5.5 hours

<h3>How to graph the inequality?</h3>

Let x represents hours babysitting and y represents hours tutoring

So, we have:

Earnings = Rate of babysitting * x + Rate of tutoring* y

This gives

Earnings = 5x + 10y

He wants to earn at least $95.

This means that:

5x + 10y ≥ 95

See attachment for the graph of the inequality

From the attached graph, two possible solutions are: (5, 7) and (8, 5.5)

This means that Carla can babysit for 5 hours and tutor for 7 hours or babysit for 8 hours and tutor for 5.5 hours