Evaluate<br> 2x - Y when x= 5, y=3

A physical education department wanted a single test of upper body strength that was easy to administer. Dips on the parallel ba

Gennadij [26K]

Answer:

24.23 ; 13.47 ; 0.782 ; p value < 0.00001 ;7.45

Step-by-step explanation:

Given that :

ΣX = 3,416, ΣY = 1,899, SDX = 8.84, SDY = 4.70, ΣZXZY = 109.416

Sample size, N = 141

Mean of X:

£X / N = 3416 / 141 = 24.23

Mean of Y:

£Y / N = 1899 / 141 = 13.47

B.) Correlation between the 2 variables :

£ZXZY / N - 1

= 109.416 / 140

= 0.782

C.)

Level of significance and p value :

T = [Rsqrt(n-2)] ÷ sqrt(1 - R²)

T = [0.782 * sqrt(139)] ÷ sqrt(1-0.782^2)

T = 14.79

P value from Tscore calculator

Df = 141 - 2 = 139 ; α = 0.05

Pvalue = 0.00001

Pvalue < α ; Hence, a significant positive relationship exists.

To obtain regression model :

Slope = £ZXZY / SDX²

m = 109.416 / 8.84^2 = 1. 4

yintercept = meanY - slope*x

yintercept = 13.47 - 1.4*24.3

yintercept = - 20.55

Equation in slope intercept form:

y = mx + c

y = 1.4x - 20.55

For x = 20

y = 1.4(20) - 20.55

y = 7.45

5 0

3 years ago

1/4(3c+5)-1/2(2c+3)=1/2<br><br> Please show some work so I can fiqure it out.

PIT_PIT [208]

So,

1/4(3c + 5) + -1/2(2c + 3) = 1/2

First, we distribute to get rid of the parentheses. (PEMDAS)
3/4c + 1 1/4 - c - 1 1/2 = 1/2

Now, we collect like terms.
-1/4c - 1/4 = 1/2

Add 1/4 to both sides.
-1/4c = 3/4

Now, multiply by the reciprocal (-4/1).
c = -3

Check your answer.

1/4(3[-3] + 5) + -1/2(2[-3] + 3) = 1/2

1/4(-9 + 5) + -1/2(-6 + 3) = 1/2

-2 1/4 + 1 1/4 + 3 - 1 1/2 = 1/2

-1 + 1 1/12 = 1/2

1/2 = 1/2

4 0

3 years ago

Read 2 more answers

Write an inequality for this situation; Kristen has a goal to walk at least 20 miles each week

saul85 [17]

Answer:

It would be the first one.

Step-by-step explanation:

When it says "at least" that means Kristen has to walk 20 miles at minimum, but she can walk more if she chooses to. Therefore in context of the problem, the greater than or equal to sign would work best.

4 0

3 years ago

The altitude a ( in feet) of a plane t minutes after lift off is given by a=3400t+600

Julli [10]

Answer:

6 minutes

Step-by-step explanation:

'a' in the formula represents altitude in feet. You are told the altitude is 21000 feet, so put that into the formula:

21000 = 3400t +600

You can solve this for t:

20400 = 3400t . . . . . subtract 600 from both sides

6 = t . . . . . . . . . . . . . . . divide both sides by 3400

The problem statement tells you that t represents minutes after lift off, so this solution means the altitude is 21000 feet 6 minutes after lift off.

The question is asking for the number of minutes after lift off that the plane reaches an altitude of 21000 feet, so this answers the question directly:

The plane is at an altitude of 21000 feet 6 minutes after lift off.

4 0

3 years ago

20.Solve the triangle: b = 100, c = 100, y = 70". If it is not possible, say so.This triangle is not solvable.Q = 40", a = 68.4,

saveliy_v [14]

Answer:

$\begin{gathered} \alpha=\text{ 40\degree} \\ \beta=\text{ 70\degree} \\ a=68.4 \end{gathered}$

Step-by-step explanation:

By the theorem of intern angles of a triangle, we know that the sum of all intern angles of a triangle must be 180°, therefore:

*There are two equal angles because there are two equal sides

$\begin{gathered} \alpha=180-70-70 \\ \alpha=\text{ 40\degree} \\ \beta=\text{ 70\degree} \end{gathered}$

Now, applying the law of sines, we can find side a. The law of sines is represented by the following equation:

$\frac{a}{\sin \alpha}=\frac{b}{\sin \beta}$

Hence, if b=100, alpha=40° and betha=70°, solve for a:

$\begin{gathered} \frac{a}{\sin (40)}=\frac{100}{\sin (70)} \\ a=\frac{100\cdot\sin (40)}{\sin (70)} \\ a=\text{ 68.4} \end{gathered}$

7 0

1 year ago

Evaluate 2x - Y when x= 5, y=3