There are about 320 million people living in the United States. Of these, how many would you predict wear corrective lenses

marin [14]

Answer:

Step-by-step explanation:

If A, B, and C are in the ratio of 2:3:5 and they are each getting some amount of money in that ratio, then to find the total amount of money they split is found in Ax + Bx + Cx and we need to solve for x. What we are told is that the smallest share = 210 and obviously A is the smallest share. Therefore,

2x = 210 and x = 105.

The total sum = 210 + 3(105) + 5(105) so

Total sum = 210 + 315 + 525

Total sum = 1050 and

C's share is 525 and

B's share is 315

6 0

3 years ago

Out of 22 players in a team, 10 of them have an average height of 1.50m while another 10 have an average height of 1.48m. The re

Sonja [21]

Answer:

1.5 meters

Step-by-step explanation:

We know that the sum of all of the data in a set = average * number of data.

Therefore, the sum of the first 10 is 1.5 * 10 = 15 meters, the sum of the second 10 is 1.48 * 10 = 14.8 meters and the sum of the last 2 is 1.6 * 2 = 3.2 meters for a total of 15 + 14.8 + 3.2 = 33 meters. This means that the mean is 33 / 22 = 1.5 meters.

6 0

3 years ago

Read 2 more answers

What is the value of p? A) 55 B) 45 C) 35 D) 125

Margarita [4]

Answer:

35

Step-by-step explanation:

just subtract 125 and 99

7 0

3 years ago

A six-foot-tall person is standing next to a flagpole. The person is casting a shadow 1 1/2 feet in length, while the flagpole i

lara31 [8.8K]

Answer: 20 ft

This problem can be solved by the Thales’s theorem, which states:

Two triangles are similar when they have equal angles and proportional sides

It should be noted that to apply Thales' Theorem, it is necessary to establish the two triangles are similar, that is, that they have the corresponding angles equal or that their sides are proportional to each other.

Now, if we measure the shadow of the flagpole and the shadow of the person, at the same moment, we can use the first Thales' Theorem to calculate the height of the flagpole, knowing the height of the person.

In this case we have two similar triangles (Figure attached) where $H$ is the height of the flagpole, $h=6 ft$ is the height of the person, $A=5 ft$ is the length of the shadow of the flagpole and $a=1\frac{1}{2}=1.5 ft$ is the length of the shadow of the person.

Having this clear, we can write the following relation with both similar triangles:

$\frac{H}{h}=\frac{A}{a}$ (1)

We know all these lengths except $H$ , which is the value we want to to find.

So, in order to approach this problem we have to find $H$ from equation (1):

$H=\frac{A}{a}h$

$H=\frac{5 ft}{1.5 ft}(6 ft)$

Then:

$H=20 ft$ >>>>>This is the height of the flagpole

4 0

3 years ago

Because of safety considerations, in May 2003 the Federal Aviation Administration (FAA) changed its guidelines for how small com

Rasek [7]

Answer:

a) The 95% confidence interval for the mean summer weight (including carry-on luggage) of Frontier Airlines passengers is between 179 and 187 pounds. This means that we are 95% sure that the mean summer weight of all Frontier Airlines passengers is between these two values.

b)

The 95% confidence interval for the mean winter weight (including carry-on luggage) of Frontier Airlines passengers is between 185.4 pounds and 194.6 pounds. This means that we are 95% sure that the mean winter weight of all Frontier Airlines passengers is between these two values.

c) They are respected, as the upper bound of both intervals is below the new FAA recommendations.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve these questions.

Question a:

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 100 - 1 = 99

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 99 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.95}{2} = 0.975$ . So we have T = 1.9842

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 1.9842\frac{20}{\sqrt{100}} = 4$

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 183 - 4 = 179 pounds.

The upper end of the interval is the sample mean added to M. So it is 183 + 4 = 187 pounds.

The 95% confidence interval for the mean summer weight (including carry-on luggage) of Frontier Airlines passengers is between 179 and 187 pounds. This means that we are 95% sure that the mean summer weight of all Frontier Airlines passengers is between these two values.

Question b:

Critical value is the same(same sample size and confidence level).

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 1.9842\frac{23}{\sqrt{100}} = 4.6$

The lower end of the interval is the sample mean subtracted by M. So it is 190 - 4.6 = 185.4 pounds.

The upper end of the interval is the sample mean added to M. So it is 190 + 4.6 = 194.6 pounds.

The 95% confidence interval for the mean winter weight (including carry-on luggage) of Frontier Airlines passengers is between 185.4 pounds and 194.6 pounds. This means that we are 95% sure that the mean winter weight of all Frontier Airlines passengers is between these two values.

c. The new FAA recommendations are 190 pounds for summer and 195 pounds for winter. Comment on these recommendations in light of the confidence interval estimates from Parts (a) and (b).

They are respected, as the upper bound of both intervals is below the new FAA recommendations.

7 0

3 years ago