{2, -1, -4, -7, ...}

The Aluminum Association reports that the average American uses 56.8 pounds of aluminum in a year. A random sample of 51 househo

Vilka [71]

Answer:

0.007

Step-by-step explanation:

We were told in the above question that a random sample of 51 households is monitored for one year to determine aluminum usage

Step 1

We would have to find the sample standard deviation.

We use the formula = σ/√n

σ = 12.2 pounds

n = number of house holds = 51

= 12.2/√51

Sample Standard deviation = 1.7083417025.

Step 2

We find the z score for when the sample mean is more than 61

z-score formula is z = (x-μ)/σ

where:

x = raw score = 61 pounds

μ = the population mean = 56.8 pounds

σ = the sample standard deviation = 1.7083417025

z = (x-μ)/σ

z = (61 - 56.8)/ 1.7083417025

z = 2.45852

Finding the Probability using the z score table

P(z = 2.45852) = 0.99302

P(x>61) = 1 - P(z = 2.45852) = 0.0069755

≈ 0.007

Therefore,the probability that the sample mean will be more than 61 pounds is 0.007

6 0

3 years ago

(9CQ) Find the distance from the balloon to the soccer fields.

almond37 [142]

Answer:

The distance from the balloon to the soccer fields = 3.6 miles ⇒ answer (b)

Step-by-step explanation:

* Let the hot air balloon at point A , the soccer fields

at point B and the football field at point C

∵ The measure of the angle of depression to the

soccer fields is 20° 15'

∴ The measure of angle B = 20° 15'

∵ The measure of the angle of depression to the

football field is 62° 30'

∴ The measure of angle C = 62° 30'

∵ The sum of measures of the interior angles of any triangle = 180°

∴ The measure of angle A = 180 - (20° 15' + 62° 30') = 97° 15'

* The distance between the balloon and the soccer field

is represented by the side AB of triangle ABC

- Use the sin Rule to find the length of side AB

∵ a/sin(A) = b/sin(B) = c/sin(C)

- a is the side opposite to angle A, b is the side opposite

to angle B and c is the side opposite to angle C

∵ AB = c ⇒ opposite to angle C

∵ The distance between the two fields = 4 miles

∴ BC = 4 miles

∵ BC = a ⇒ opposite to angle A

∴ 4/sin(97° 15') = c/sin(62° 30')

∴ c = (4 × sin(62° 30')) ÷ sin(97° 15')

∴ c = 3.6 miles

∴ The distance from the balloon to the soccer fields = 3.6 miles

answer (b)

4 0

3 years ago

A cable for a power transformer forms

posledela

Answer:

32 ft

Step-by-step explanation:

From the diagram, the side opposite the 60° angle is 28 feet.

We are looking for the approximate length of the cable.

The approximate length of the cable is the hypotenuse of the triangle shown.

Recall the sine ratio from SOH-CAH-TOA

Which means Sine of the angle is Opposite/Hypotenuse

Let the hypotenuse be h, then we have:

$\sin(60) = \frac{28}{h}$

$0.866 = \frac{28}{h}$

$h = \frac{28}{0.866}$

$h = 32.33$

The length of the cable is approximately 32 feet

3 0

3 years ago

What is an equation of a line with a slope -2/3 and a y intercept of -4 ?

Gnesinka [82]

Written in slope intercept form y=mx+b.......m is the slope.......b is the y intercept or where the line crosses the y axis

y=-2/3x - 4

6 0

3 years ago

The diagram shows a 3 cm x 5 cm x 4 cm cuboid

Rainbow [258]

Answer:

a) The length of segment AC is approximately 5.83 centimeters.

b) The angle ACD is approximately 34.5º.

Step-by-step explanation:

a) Since $AB \perp BC$ , the length of segment $AC$ is determined by Pythagorean Theorem, that is:

$AC = \sqrt{(5\,cm)^{2}+(3\,cm)^{2}}$

$AC \approx 5.831\,cm$

The length of segment AC is approximately 5.831 centimeters.

b) Since $AB \perp BC \perp AD$ , the length of segment $AD$ is determined by this Pythagorean identity:

$AD = \sqrt{(3\,cm)^{2}+(5\,cm)^{2}+(4\,cm)^{2}}$

$AD \approx 7.071\,cm$

The angle ACD is determined by the following trigonometric expression:

$\cos C = \frac{AC}{CD}$

$\cos C = \frac{5.831\,cm}{7.071\,cm}$

$\cos C = 0.825$

$C = \cos^{-1} 0.825$

$C \approx 34.448^{\circ}$

The angle ACD is approximately 34.448º.

4 0

3 years ago