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3 years ago

A teacher graded the tests for each of her students. She calculated a mean grade of 80 and a

Mathematics

1 answer:

son4ous [18]3 years ago

7 0

Answer:

Katrina got 86 in her test

Step-by-step explanation:

given

mean = 80

standard deviation = 3

z-score = 2

Let score of Katrina = x

Recall z-score is calculated by

z-score = (x-mean) / standard deviation

substitute values and solve for x

2 = (x-80)/3

x-80=6

x = 86

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9d-2d+4d=32 <br> Need help

Luden [163]

Answer:

=2.90d

Step-by-step explanation:

i think is that hope IT help

8 0

3 years ago

Among 18 students in a room, 7 study mathematics, 10 study science, and 10 study computer programming. Also, 3 study mathematics

tatyana61 [14]

Answer:

2 students study none of the subjects.

Step-by-step explanation:

Consider the attached venn diagram. First, we place that 1 student studies the three subjects. Then, we notice that 3 students study math and science, then 2 students study math and science only, since we have 1 that studies the three subjects. In the same fashion, we have that 3 students study Math and computer programming only (since they are 4 in total). Note that since 7 students study math, and we already have 6 students in our count in the math subject this implies that 1 student studies only math (the total number of students inside the math circle must add to 7).

We also have that 4 students study science and computer programming only. Which implies that we must have 3 students that study science only (10 students that study science in total) and 2 students study computer programming (for a total of 10 students). The total number of students that study none is the total number of students (18) minus the amount of students that is inside the circles (16) which is 2.

8 0

3 years ago

Read 2 more answers

HELP!!! Picture included :).

jasenka [17]

Answer:

(A'B'): 3 1/2 IN.

(D'E'): 2 1/2 IN.

(R'S'): 4 IN.

Step-by-step explanation:

Just slice the numbers in half

Also i took the test.

6 0

3 years ago

Write the unit fraction depicted in the model as a percent.<br><br> One-fourth

yan [13]

Answer:

1/4×100 = 0.25×100

= 25%

Thus,

1/4 = 25%

Step-by-step explanation:

Given the fraction

1/4

In order to write the fraction 1/4 as a percent, all we need is to multiply 1/4 by 100.

i.e.

1/4×100 = 0.25×100

= 25%

Therefore, we conclude that:

1/4 = 25%

4 0

3 years ago

Pentagon ABCDE and pentagon A″B″C″D″E″ are shown on the coordinate plane below:

erastova [34]

The transformations that are applied to pentagon ABCDE to create A"B"C"D"E" are:

1) Translation (x, y) → (x + 8, y + 2)

2) Reflection across the x-axis (x, y) → (x, -y)

So, the overall transformation given in the graph is (x, y) → {(x + 8), -(y + 2)}.

<h3>What are the transformation rules?</h3>

The transformation rules are:

Reflection across x-axis: (x, y) → (x, -y)
Reflection across y-axis: (x, y) → (-x, y)
Translation: (x, y) → (x + a, y + b)
Dilation: (x, y) → (kx, ky)

<h3>Calculation:</h3>

The pentagons in the graph have vertices as

For the pentagon ABCDE: A(-4, 5), B(-6, 4), C(-5, 1), D(-2, 2), and (-2, 4)

For the pentagon A"B"C"D"E": A"(4, -7), B"(2, -6), C"(3, -3), D"(6, -4), and E"(6, -6)

Consider the vertices A(-4, 5) from the pentagon ABCDE and A"(4, -7) from the pentagon A"B"C"D"E".

Applying the Translation rule for the pentagon ABCDE:

The rule is (x, y) → (x + a, y + b)

So, the variation is

-4 + a = 4

⇒ a = 4 + 4 = 8

5 + b = 7

⇒ b = 7 - 5 = 2

So, the pentagon ABCDE is translated by (x + 8, y + 2).

Applying the Reflection rule for the translated pentagon:

The translated pentagon has vertices (x + 8, y + 2).

When applying the reflection across the x-axis,

(x + 8, y + 2) → {(x + 8), -(y + 2)}

Therefore, the complete transformation of the pentagon ABCDE to the pentagon A"B"C"D"E" is (x, y) → {(x + 8), -(y + 2)}

Verification:

A(-4, 5) → ((-4 + 8), -(5 + 2)) = (4, -7)A"

B(-6, 4) → ((-6 + 8), -(4 + 2)) = (2, -6)B"

C(-5, 1) → ((-5 + 8), -(1 + 2)) = (3, -3)C"

D(-2, 2) → ((-2 + 8), -(2 + 2)) = (6, -4)D"

E(-2, 4) → ((-2 + 8), -(4 + 2)) = (6, -6)E"

Learn more about transformation rules here:

brainly.com/question/4289712

#SPJ1

5 0

2 years ago