All categories

2 years ago

Help me with this assignment problem

Mathematics

1 answer:

Rus_ich [418]2 years ago

3 0

Answer:

1/27

step by step explanation

1x1x1=1

3x3x3=27

You might be interested in

A college job placement office collected data about students’ GPAs and the salaries they earned in their first jobs after gradua

frez [133]

Answer:

X is the GPA

Y is the Salary

Standard deviation of X is 0.4

Standard deviation of Y is 8500

E(X)=2.9

E(Y)=47200

We are given that The correlation between the two variables was r = 0.72

a) $y = a+bx$

$b = \frac{\sum(x_i-\bar{x})(y_i-\bar{y})}{\sum(x_i-\bar{x})^2} = \frac{r \times \sqrt{var(X) \times Var(Y)}}{Var(X)} = \frac{0.72 \times \sqrt{0.4^2 \times 8500^2}}{0.4^2} = 15300$

$a=y-bx = 47200-(15300 \times 29) = 2830$

So, slope = 15300

Intercept = 2830

So, equation : $y = 2830+15300x$

b) Your brother just graduated from that college with a GPA of 3.30. He tells you that based on this model the residual for his pay is -$1880. What salary is he earning?

$y = 2830+15300 \times 3.3 = 53320$

Observed salary = Residual + predicted = -1860+53320 = 51440

c)) What proportion of the variation in salaries is explained by variation in GPA?

The proportion of the variation in salaries is explained by variation in GPA = $r^2 = (0.72)^2 =0.5184$

8 0

2 years ago

Lupe’s Construction is building a rectangular house that is 16 feet longer than it is wide. They will be putting a 3-foot wide s

mr Goodwill [35]

Answer:

The length of the four pieces of protective strip is 96 feet

Step-by-step explanation:

Let the w be the width of the rectangular house and L is length. Since L = w + 16, its perimeter P = 2(w + L)

= 2(w + w + 16)

= 2(2w + 16)

Since the perimeter of the house P = 136 feet,

136 = 2(2w + 16)

dividing through by 2, we have

136/2 = (2w + 16)

68 = (2w + 16)

collecting like terms, we have

68 - 16 = 2w

52 = 2w

dividing through by 2, we have

w = 52/2

w = 26 feet.

Now, since the side walk is 3 foot wide all around, the width of the house plus sidewalk = w + 3 and the length of the house plus sidewalk = L + 3 = w + 16 + 3 = w + 19.

So, the perimeter of the house plus sidewalk which is the perimeter of the four pieces of protective strip is P' = 2(w + 3 + w + 19)

= 2(w + 22)

= 2(26 + 22)

= 2(48)

= 96 feet

So, the length of the four pieces of protective strip is 96 feet.

5 0

3 years ago

help please! Darren is finding the equation in the form y = m x + b for a trend line that passes through the points (2, 18) and

andrezito [222]

Answer: d) 14

Step-by-step explanation:

Equation of a line passing through (a,b) and (c,d):

$(y-b)=\dfrac{d-b}{c-a}(x-a)$

Equation of a line passing through (2, 18) and (–3, 8):

$(y-18)=\dfrac{8-18}{-3-2}(x-2)\\\\\Rightarrow\ (y-18)=\dfrac{-10}{-5}(x-2)\\\\\Rightarrow\ (y-18)=2(x-2)\\\\\Rightarrow\ y-18=2x-4\\\\\Rightarrow\ y=2x-4+18\\\\\Rightarrow\ y=2x+14$