4. Which expression represents "4 less than the product of 2 and a number e"?

The dotplot below displays the difference in scores for 18 games between a high school soccer team and its opponent.

kiruha [24]

Answer: Choice D

In two games, the team lost to the opponent by 1 goal.

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Explanation:

Negative scores indicate the team lost, and the absolute value of those values represent how much of a loss.

So a difference of -1 means the team lost by 1 point.

We have 2 dots over this value, so there are 2 occasions where the team lost to the opponent by 1 goal.

An example would be that say the team scored 3 goals and the opponent scored 4 goals. So we have a differential of 3-4 = -1. The order is important because we would <u>not</u> say 4-3 = 1.

6 0

2 years ago

Bas_tet [7]

Answer:

a) We reject H₀ We find difference between the mean of the two groups

b) we accept H₀ : There is no statistical difference ( in the scale of pain) when the difference in samples means is 1

Step-by-step explanation:

Group 1: Only with educational material

Sample size n₁ = 42

Sample mean x₁ = 3,2

Sample standard deviation s₁ = 2,3

Group 2: With exercises with the treatment of individuals

Sample size n₂ = 42

Sample mean x₂ = 5,2

Sample standard deviation s₂ = 2,3

Test Hypothesis

Null Hypothesis H₀ x₂ - x₁ = 0 or x₁ = x₂

Alternative Hypothesis Hₐ x₂ - x ₁ > 0 or x₂ > x₁

Significance level α = 0,01

Sample sizes are n₁ = n₂ > 30

We use z-test

for α = 0,01 z(c) ≈ 2,32

To calculate z(s)

z(s) = ( x₂ - x₁ ) / √ (2,3)²/42 + (2,3)²/42

z(s) = ( 5,2 - 3,2 )/ √0,2519

z(s) = 2 / 0,5

z(s) = 4

Comparing z(s) and z(c)

z(s) > z(c)

z(s) is in the rejection region. We reject H₀ the true average pain level for the control condition exceeds that for the treatment condition.

b) Does the true average pain level for the control condition exceed that for the treatment condition by more than 1.

In this case

z( s) = x₂ - x₁ / 0,5

z(s) = 1 /0,5

z(s) = 2

Comparing z(s) and z(c) now

z(s) < z(c) 2 < 2,32

And z(s) is in the acceptance region ( for the same significance level) and we should accept H₀ equivalent to say that the two groups statistical have the same mean

5 0

3 years ago

1. A boat is 18 ft away from a point perpendicular to the shoreline. A person stands at a point down the shoreline so that a 68°

slega [8]

Answer:

19.4 feet

Step-by-step explanation:

When calculating distances using perpendicular angles, we use trig functions such as Sin, Cos, and Tan.

Sine is defined in a perpendicular triangle as the ratio of the opposite side to the angle over the hypotenuse.
Cosine is defined in a perpendicular triangle as the ratio of the adjacent side to the angle over the hypotenuse.
Tangent is defined in a perpendicular triangle as the ratio of the opposite side over the adjacent side.

Because our angle and know side value are across from each other and we need to know the hypotenuse, we chose to use Sine.

We set up the equation $sin (68) = \frac{18}{h}$ .

We isolate h by multiplying h across the equal sign and dividing sin (68) across as well. $sin (68) = \frac{18}{h}\\hsin (68) = \frac{18}{h}*h\\hsin (68) = 18\\\frac{hsin (68)}{sin (68)} =\frac{18}{sin (68)} \\$

And finally we have $h=\frac{18}{sin (68)}$ . We input to calculator.

$h=\frac{18}{0.92718} \\h=19.4 feet$

See the attached picture below showing the shore with the boat out at sea and the position of the person.

8 0

3 years ago

What is commutative property in rational number ? please explain.

slavikrds [6]

Answer:

Commutative property of addition of rational numbers: Two rational numbers can be added in any order. Thus for any two rational numbers a/b and c/d, we have. (a/b + c/d) = (c/d + a/b)

4 0

2 years ago

If g(x) = 5x2^2 - 10x + 9 and h(x) = -3x3^3+ 5x - 6, find g(x) - h(x)?

AnnZ [28]

Answer:

B) $g(x) - h(x) = 3x^3 - 5x^2 - 15x + 15$