15 is 30% of what number?

A plastics manufacturer has developed a new type of plastic trash can and proposes to sell them with an unconditional 6-year war

gtnhenbr [62]

Answer:

since -3.73 is less than 1.645, we reject H₀.

Therefore this indicate that the proposed warranty should be modified

Step-by-step explanation:

Given that the data in the question;

p" = 13/20 = 0.65

Now the test hypothesis;

H₀ : p = 0.9

Hₐ : p < 0.9

Now lets determine the test statistic;

Z = (p" - p ) / √[p×(1-p)/n]

= (0.65 - 0.9) /√[0.9 × (1 - 0.9) / 20]

= -0.25 / √[0.9 × 0.1 / 20 ]

= -0.25 / √0.0045

= -0.25 / 0.067

= - 3.73

Now given that a = 0.05,

the critical value is Z(0.05) = 1.645 (form standard normal table)

Now since -3.73 is less than 1.645, we reject H₀.

Therefore this indicate that the proposed warranty should be modified

3 0

2 years ago

It is important that face masks used by firefighters be able to withstand high temperatures because firefighters commonly work i

USPshnik [31]

Answer:

The 93% confidence interval for the true proportion of masks of this type whose lenses would pop out at 325 degrees is (0.3154, 0.5574). This means that we are 93% sure that the true proportion of masks of this type whose lenses would pop out at 325 degrees is (0.3154, 0.5574).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

For this problem, we have that:

$n = 55, \pi = \frac{24}{55} = 0.4364$

93% confidence level

So $\alpha = 0.07$ , z is the value of Z that has a pvalue of $1 - \frac{0.07}{2} = 0.965$ , so $Z = 1.81$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4364 - 1.81\sqrt{\frac{0.4364*0.5636}{55}} = 0.3154$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4364 + 1.81\sqrt{\frac{0.4364*0.5636}{55}} = 0.5574$

The 93% confidence interval for the true proportion of masks of this type whose lenses would pop out at 325 degrees is (0.3154, 0.5574). This means that we are 93% sure that the true proportion of masks of this type whose lenses would pop out at 325 degrees is (0.3154, 0.5574).

8 0

3 years ago

How many 1/2 cup servings are in the 7/8 cups of peanut butter

Sunny_sXe [5.5K]

This is more or less how you write the question.
$\frac{ \frac{7}{8} } { \frac{1}{2} }$

To solve it invert the 1/2 and multiply.
$\frac{7 * 2}{8 * 1}$

Which gives you 14 /8 whis is 1 3/4 cups.

8 0

3 years ago

SOMEONE HURRY QUICK THIS IS TIMED

Marat540 [252]

This would be a graph, a function is a straight line while a graph can be a scatter plot or something similar

3 0

3 years ago

At the market, 2.4 pounds of carrots cost $1.68 and 1.8 pounds of broccoli cost $1.53. How much more does 1 pound of broccoli co

Greeley [361]

For calculating that, you have to find the unit rate first;

2.4 pound carrot = $1.68

1 pound carrot = $1.68/2.4 = $0.7

1.8 pound broccoli = $1.53

1 pound broccoli = $1.53/1.8 = $0.85

So, it would be = $0.85 - $0.7 = $0.15

SO, YOUR ANSWER IS $0.15

5 0

3 years ago