Please help me please!!!!!

In a recent Dunkin Donuts (DD) commercial, it states that 58% of Americans prefer to drink their coffee. Of the five hundred ran

Sergio [31]

Answer:

We conclude that the proportion of Americans who prefer to drink DD coffee is actually more than what was advertised.

Step-by-step explanation:

We are given that in a recent Dunkin Donuts (DD) commercial, it states that 58% of Americans prefer to drink their coffee.

Of the five hundred randomly selected people who were asked if they preferred DD coffees, 325 said they did.

Let p = proportion of Americans who prefer to drink DD coffee

SO, Null Hypothesis, $H_0$ : p $\leq$ 58% {means that the proportion of Americans who prefer to drink DD coffee is actually less than or equal to what was advertised}

Alternate Hypothesis, $H_A$ : p > 58% {means that the proportion of Americans who prefer to drink DD coffee is actually more than what was advertised}

The test statistics that will be used here is One-sample z proportion statistics;

T.S. = $\frac{\hat p-p}{{\sqrt{\frac{\hat p(1-\hat p)}{n} } } } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of people who prefer to drink DD coffee in a sample of 500 people = $\frac{325}{500}$ = 65% or 0.65

n = sample of people = 500

So, test statistics = $\frac{0.65-0.58}{{\sqrt{\frac{0.65(1-0.65)}{500} } } } }$

= 3.282

Now at 0.05 significance level, the z table gives critical value of 1.6449 for right-tailed test. Since our test statistics is more than the critical value of z so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region.

Therefore, we conclude that the proportion of Americans who prefer to drink DD coffee is actually more than what was advertised.

6 0

3 years ago

The expressions below model different possibilities for the area of a pool. Identify which of the following expressions have at

Anna007 [38]

<h3>Answer: Choice B is correct</h3>

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Explanation:

Use a graphing tool like GeoGebra, Desmos, or your graphing calculator to plot each expression given as a separate y equation. Four parabolas should result.

The x intercept is the same as the root or zero of a function.

You should find that only choice B has a root thats larger than 4. That specific root being x = 7.

----------------------------

A non-graphing approach:

You can use the quadratic formula or the factoring method to find the roots.

For choice A, it factors to (x+5)(x+6) = 0. The roots are x = -5 and x = -6 which aren't greater than 4. So we cross choice A off the list. Choices C and D are similar stories.

On the other hand, choice B factors to (x-7)(x+2) = 0 and it has roots of x = 7 and x = -2. This is another way to see why choice B is the answer.

Here are the steps for the quadratic formula for choice B

$x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x = \frac{-(-5)\pm\sqrt{(-5)^2-4(1)(-14)}}{2(1)}\\\\x = \frac{5\pm\sqrt{81}}{2}\\\\x = \frac{5\pm9}{2}\\\\x = \frac{5+9}{2} \ \text{ or } \ x = \frac{5-9}{2}\\\\x = \frac{14}{2} \ \text{ or } \ x = \frac{-4}{2}\\\\x = 7 \ \text{ or } \ x = -2\\\\$

The quadratic formula is handy in case factoring is either not possible, or guess-and-check is too lengthy of a process. As you can probably tell, we could use the quadratic formula's results to help construct the factored form.

8 0

3 years ago

A. (0,-1); maximum B. (-1,0); minimum C. (-1,0); maximum D. (0,-1); minimum

Zolol [24]

Hey! This is a maximum because that's where it peaks. It doesn't go any higher from there so the coordinates are (0,-1) or A.

5 0

4 years ago

What is 20% decreased of 1.75

Fantom [35]

Answer:

1.4

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

The length of a rectangular frame is 12 inches, and the width of the frame is 5

Lorico [155]

Answer:

17 inches

Step-by-step explanation:

6 0

3 years ago