How much more is 3/8 gallon than 1/4 gallon?

) for a particular diamond mine, 77% of the diamonds fail to qualify as "gemstone grade". a random sample of 112 diamonds is ana

sweet [91]

We use the z statistic:

z = (x – u) / s

But first let us calculate the standard deviation s, sample x and mean u.

s = sqrt (n p q)

s = sqrt (112 * 0.77 * (1 – 0.77))

s = 4.45

x = 0.81 * 112 = 90.72

u = 0.77 * 112 = 86.24

So the z score is:

z = (90.72 – 86.24) / 4.45

z = 1.00

From the standard tables, the P value at z = 1.00 using right tailed test is:

P = 0.1587 = 15.87%

7 0

1 year ago

The number of acres in a region cleared for farming follows the formula a = f (t) = 2t2 where t is the number of months since th

Anit [1.1K]

we are given

$a=f(t)=2t^2$

we can use average rate of change formula from t=a to t=b

$A=\frac{f(b)-f(a)}{b-a}$

Here, we are given from t=1 to t=4

so, we will get formula as

$A=\frac{f(4)-f(1)}{4-1}$

now, we can plug values

$A=\frac{2(4)^2-2(1)^2}{4-1}$

now, we can simplify it

$A=10$

the average rate of change in the number of acres cleared for farming between t = 1 and t = 4 is 10 acres/ month.............Answer

6 0

2 years ago

We suspect that automobile insurance premiums (in dollars) may be steadily decreasing with the driver's driving experience (in y

ANTONII [103]

Answer:

D) a chi square test for independence.

Step-by-step explanation:

Given that we suspect that automobile insurance premiums (in dollars) may be steadily decreasing with the driver's driving experience (in years), so we choose a random sample of drivers who have similar automobile insurance coverage and collect data about their ages and insurance premiums.

We are to check whether two variables insurance premiums and driving experience are associated.

Two categorical variables are compared for different ages and insurance premiums.

Hence a proper test would be

D) a chi square test for independence.

8 0

1 year ago

Researchers from Dartmouth Medical School conducted a study in 2003 to look at the connection between watching actors smoking in

docker41 [41]

Answer:

The 95% confidence interval for the proportion of adolescents who tried smoking for the first time because of exposure to smoking in the movies is (0.37, 0.40).

Step-by-step explanation:

A confidence interval is an interval estimate of the population parameter. The confidence interval has a certain probability of consisting the true value of the parameter.

The (1 - α) % confidence interval for the population proportion (p) is given by:

$CI=\hat p\pm z_{\alpha/2}\times \sqrt{\frac{\hat p(1-\hat p)}{n}}$

The information provided is:

$n = 6522\\\hat p=0.38\\z_{\alpha/2}=z_{0.05/2}=z_{0.025}=1.96$

*Use a z-table for the critical value.

Construct the 95% confidence interval for the proportion of adolescents who tried smoking for the first time because of exposure to smoking in the movies as follows:

$CI=\hat p\pm z_{\alpha/2}\times \sqrt{\frac{\hat p(1-\hat p)}{n}}\\=0.38\pm 1.96\times \sqrt{\frac{0.38(1-0.38)}{6522}}\\=0.38\pm 0.0118\\=(0.3682, 0.3918)\\\approx (0.37, 0.40)$

Thus, the 95% confidence interval for the proportion of adolescents who tried smoking for the first time because of exposure to smoking in the movies is (0.37, 0.40).

8 0

1 year ago

Ginger Smith was seen in Dr. Sampson's office today for an allergic reaction to a prescribed drug. Total charges today are $100.

Anna71 [15]

Answer: Ginger Smith will have to pay $23.00

Step-by-step explanation:

When we talk about a Health Insurance, the Allowed amount $A$ is the maximum amount the Health Insurance company will cover for health care services.

So, if the health care provider charges more than this allowed amount (as in this situation with Ginger Smith), Ginger will have to pay the difference $D$ , which is calculated by:

$D=T-A$

$T=\$100.00$ are the total charges

$A=\$77.00$ is the allowed amount

$D=\$100.00-\$77.00$

$D=\$23.00$ This is the difference Ginger Smith will have to pay

6 0

1 year ago