30 points and brainliest help me out please. 5th grade

The professor of a business statistics class wanted to find out the average amount of time per week her students spent studying

zhenek [66]

Answer:

Cluster sample

Step-by-step explanation:

This is an example of a cluster sample. In a cluster sample, the examiner divides the population into groups (each one of these groups is called a cluster) and once the examiner has these clusters, takes one of them and recollects the data from ALL the members of that cluster. In this case, the teacher divided the class in 3 different groups and then selects one of these groups and asks the average amount of time per week he/she spent studying.

6 0

2 years ago

The length of a rectangle is 4 cm less than it’s width. If the area of the rectangle is 165 cm^2. What are the dimensions of the

Monica [59]

Answer:

The dimensions are 11 cm by 15 cm

Step-by-step explanation:

Area of a rectangle = (length)(width).

Let L represent the length and W the width.

Since L = W - 4, we have

Area of rectangle = (W - 4)W = 165 cm^2.

Thus, w^2 - 4W - 165 = 0. We can solve for W using the quadratic formula:

a = 1, b = -4 and c = -165. Thus,

-(-4) ± √ [ (-4)² - 4(1)(-165) ]

W = ---------------------------------------

2

4 ± √ [16 + 660 ]

W = ------------------------------

2

4 ± √ [ 676 ] 4 ± 26

W = ----------------------- = W = ------------- = W = 2 ± 13

2 2

Thus, W is 2 + 13 = 15. It cannot be negative, so we discard 2 - 13 = -11.

If the width, W, is 15, then the length is 4 less, or L = 11.

The dimensions are 11 cm by 15 cm

6 0

3 years ago

Eric was rock climbing. At one point, he stopped and climbed straight down 2\dfrac{1}{2}2

nikitadnepr [17]

The equation that matches the given situation is $-2\frac{1}{2}+6\frac{3}{4}=?$ . So, after two moves, Eric's elevation changed $4\frac{1}{4}$ meters above.

We know that in mathematics, subtraction means removing something from a group or a number of things. What is left in the group gets smaller when we subtract. The minuend is the first element we use. The subtrahend is the part that is being removed. The difference is the portion that remains after subtraction.

Assume that "negative" means climbing down and "positive" means climbing up. We must locate the elevation change in this area.

Given that Eric climbed straight down $2\frac{1}{2}$ meters. So we can write $-2\frac{1}{2}$ .

Again Eric climbed straight up $6\frac{3}{4}$ meters. So, we can write $6\frac{3}{4}$ .

Then the change = $-2\frac{1}{2}+6\frac{3}{4}$

= $-\frac{(2*2+1)}{2}+\frac{6*4+3}{4}$

= $-\frac{5}{2} +\frac{27}{4}$

= $\frac{-(5*2)+27}{4}$

= $\frac{-10+27}{4}$

= $\frac{17}{4}$

= $\frac{4*4+1}{4}$

= $4\frac{1}{4}$

Therefore, the equation that matches the given situation is $-2\frac{1}{2}+6\frac{3}{4}=?$ . So, after two moves, Eric's elevation changed $4\frac{1}{4}$ meters above.

Learn more about subtraction here -

brainly.com/question/24116578

#SPJ10

7 0

1 year ago

Can someone help me

jeka57 [31]

Number one is really easy just set it up in proportions. 420 over x and 7 hours over 24 cause you know there 24 hours in a day and then cross division and simplify. I think.

8 0

3 years ago

Andrea is selling candles for a fundraiser. She spent $50 on supplies for making the candles. She plans to sell the

Debora [2.8K]

The independent variable would be the Candles she sells for $10

3 0

3 years ago