Suppose 140 geology students measure the mass of an ore sample. Due to human error and limitations in the reliability of theâ balance, not all the readings are equal. The results are found to closely approximate a normalâ curve, with mean 82 g and standard deviation 3 g. Use the symmetry of the normal curve and the empirical rule as needed to estimate the number of students reporting readings between 79 g and 85 g

Answer:

i dont know i tried really really hard i wish i could help

Step-by-step explanation:

Did I read your handwriting correctly? Is this what you wrote? If so the answer is:

[tex](x( {x}^{2} - 2xy - {y}^{2} ) \div (x + y)(x - y)^{2} [/tex]

Answer:

66°

Step-by-step explanation:

mJK = ( 6x - 45 )°

mJH = ( x + 20 )°

mJK = mJH

6x - 45 = x + 20

5x = 65

x = 13

mHK = ( x + 20 )° + ( 6x - 45 )°

mHK = 2 × 33° = 66 °

Answer:

1st option

Step-by-step explanation:

A verical line parallel to the y- axis has equation

x = c ( c is the value of the x- coordinates the line passes through )

thus the x- coordinates are the same

Answer:

y=x-6

Step-by-step explanation:

Answer:

a) Mean shoe size = 7.8

b) 8.8, 9.8 and 10.8

c) see attached

d) Shoe size

Step-by-step explanation:

[tex]\sf Mean \ \mu= 7.8[/tex]

[tex]\sf Standard \ deviation \ \sigma= 1[/tex]

Therefore,

[tex]\sf 1 \sigma=\mu+1 \sigma=7.8+1=8.8\\\sf 2 \sigma=\mu+2 \sigma=7.8+2 \cdot 1=9.8\\\sf 3 \sigma=\mu+3 \sigma=7.8+3 \cdot 1=10.8[/tex]

Answer:

the 2nd one

Step-by-step explanation:

i did the test and got correct

Answer:

(2, 4).

Step-by-step explanation:

For y = -x  the transform is:

( x, y )  reflects to (-y, - x)

So (-4, -2) reflects to (2, 4)

Answer:

8 cm

Explanation:

A = 1/2 × b × h.

28 = 1/2*b*7

56=7b

8=b

Answer:

A) 38,000

B) 28.6%

Step-by-step explanation:

Answer:

16000280

Step-by-step explanation:

hope this helps.

Answer: See attached

Step-by-step explanation:

    "Root 9.8" means the square root of 9.8, [tex]\sqrt{9.8}[/tex].

    Since we are being asked to find it on the number line, I am guessing they want us to estimate. We know that the square root of 9, [tex]\sqrt{9}[/tex], is equal to 3. Since 9.8 is slightly bigger than 9, the square root of 9.8 will be a little bit over 3.

   Want to confirm? Using a calculator for the square root of 9.8 gives us 3.13.

Answer:

You didn't include the question, so people are unable to help you.

Step-by-step explanation:

she played for about 1 hour 29 minutes

Answer:

1 hour and 29 minutes or 89 minutes

Answer:

Search it up on the internet

Step-by-step explanation:

hope this helps

Answer:

b they are perpendicular

Step-by-step explanation:

they intersect each other at point D

Using the slope concept, it is found that the distance traveled from point A to point B was of 12060.8 ft.

The slope is given by the vertical change divided by the horizontal change, and it's also the tangent of the angle of depression.

At point A, the vertical change is of 7225 feet, with an angle of 19º, hence:

[tex]\tan{19^\circ} = \frac{7225}{x_A}[/tex]

[tex]x_A = \frac{7225}{\tan{19^\circ}}[/tex]

[tex]x_A = 20982.9[/tex]

At point B, the vertical change is of 7225 feet, with an angle of 39º, hence:

[tex]\tan{39^\circ} = \frac{7225}{x_B}[/tex]

[tex]x_B = \frac{7225}{\tan{39^\circ}}[/tex]

[tex]x_B = 8922.1[/tex]

The distance in feet is given by:

[tex]d = x_A - x_B = 20982.9 - 8922.1 = 12060.8[/tex]

More can be learned about the slope concept at https://brainly.com/question/18090623

Answer:

Fraction: 13/30

Decimal: 0.43

Percentage: 43%

Answer:

B. 86.625

Step-by-step explanation:

To find the volume of a shape the formula is this, length x width x height. 5.5 x 4.5 x 3.5 = 86.625.

Answer:

x = 30

Step-by-step explanation:

2x - 6

-----------  =  9

    6

2x - 6

-----------  =  9(6)

    6(6)

2x - 6 = 54

     +6    +6

2x = 60

÷2    ÷2

x = 30

I hope this helps!

Step-by-step explanation:

2x+98=180° (angles in straight line )

2x=180-98

x=2/2

x=1

Answer:

x = 41

Step-by-step explanation:

the 2 angles are adjacent and sum to 180° , that is

2x + 98 = 180 ( subtract 98 from both sides )

2x = 82 ( divide both sides by 2 )

x = 41

Answer:

pi/4

Step-by-step explanation:

diameter of the circle is 2
area of circle = pi * r^2
A = pi * 1^2
A = 1pi
1/4th of the area so
pi/4

Answer:

31° F

Step-by-step explanation:

Although it is hard to see, Saturday's low temperature is approximately 31°. This is evident in its relative position to Friday's temperature, which measures 30° F -- Saturday is just one degree higher.

Hope this helps!

Answer:31

Step-by-step explanation:

89.09% of books will weigh 11 pounds or more, then the number of books will be 129.

The z-score is a numerical measurement used in statistics to refer to how much a given value differs from the standard deviation.

The weights of books in a bookcase are normally distributed with a mean of 11.6 pounds and a standard deviation of 1.3 pounds. There are 136 books on the bookshelf.

Then the z-score when the books will weigh 11 pounds or more will be

[tex]z= \frac{11-13.5}{2.3} \\\\z= -1.0869[/tex]

Then the probability will be

[tex]P(x > 11) = 1-P(x < 11 ) = 0.8909[/tex]

89.09% of books will weigh 11 pounds or more, then the number of the books will be

=145 × 0.8909

=129.1805 ≈ 129

More about the z-score link is given below.

brainly.com/question/15016913

#SPJ1

Answer:

Step-by-step explanation:

Isolate the term of x and y from one side of the equation.

⇒ x+2y=11

⇒ x=11-2y

Substitute.

4(11-2y)-y=8

Solve.

Distributive property:

⇒ A(B+C)=AB+AC

4(11-2y)

4*11=44

4*2=8

Rewrite the problem down.

44-9y=8

Subtract by 44 from both sides.

44-9y-44=8-44

Solve.

-9y=-36

Divide by -9 from both sides.

-9y/-9=-36/-9

Solve.

-36/-9=4

y=4

Substitute of y=4.

⇒ x=11-2*4

Use order of operations.

PEMDAS stands for:

11-2*4

Multiply.

2*4=8

Rewrite the problem down.

11-8

Subtract.

11-8=3

x=3

I hope this helps you! Let me know if my answer is wrong or not.

Answer:

Step-by-step explanation:

Answer:

Step-by-step explanation:

Rotate triangle DEF 90° and translate it up 1 point, and left 2 points.

Step-by-step explanation:

what is the problem ? you teacher gave you even the conversion rates in the question.

so, when 1 gallon = 3.79 liters, then how much is 4 gallons ?

4 gallons is 4 times 1 gallon. so, of course, we need to apply the same factor to the other side too.

4 gallons = 4×3.79 = 15.16 ≈ 15 liters

and e do the same for all the other table elements :

8 liters = 8×0.26 = 2.08 ≈ 2 gallons

12.5 liters = 12.5×0.26 = 3.25 ≈ 3 gallons

6 gallons = 6×3.79 = 22.74 liters ≈ 23 liters

Answer:

It depends how much percent the test is worth on your grade, and how much test grades you have. It would definitely raise to at least an 83 though.

Let's check

Total

Grade

Answer:

104+16π

Step-by-step explanation:

Triangle Formula is bh1/2

Rectangle is lxw

Semicircle is 1/2 π r^2