A math professor notices that scores from a recent exam are normally distributed with a mean of 61 and a standard deviation of 8. Answer the following questions using integer values.
(a) What score do 25% of the students exam scores fall below?
And, the professor decides to grade on a curve. If he wants .15% of the students to get an A, what is the minimum score required.
I have tried a "calculator" I found online and the answers it provided gave me 50% credit and I don't know which answer is correct as I don't know how to do the actual calculation.
I would appreciate referral to any valid resources as it has been many, many years since I took a math class.
(b) Suppose the professor decides to grade on a curve. If the professor wants 0.15% of the students to get an A, what is the minimum score for an A?

Answers

Answer 1

Answer:

a) 25% of the students exam scores fall below 55.6.

b) The minimum score for an A is 84.68.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 61 and a standard deviation of 8.

This means that [tex]\mu = 61, \sigma = 8[/tex]

(a) What score do 25% of the students exam scores fall below?

Below the 25th percentile, which is X when Z has a p-value of 0.25, that is, X when Z = -0.675.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]-0.675 = \frac{X - 61}{8}[/tex]

[tex]X - 61 = -0.675*8[/tex]

[tex]X = 55.6[/tex]

25% of the students exam scores fall below 55.6.

(b) Suppose the professor decides to grade on a curve. If the professor wants 0.15% of the students to get an A, what is the minimum score for an A?

This is the 100 - 0.15 = 99.85th percentile, which is X when Z has a p-value of 0.9985. So X when Z = 2.96.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]2.96 = \frac{X - 61}{8}[/tex]

[tex]X - 61 = 2.96*8[/tex]

[tex]X = 84.68[/tex]

The minimum score for an A is 84.68.


Related Questions

pls help!
how many faces does it have?

Answers

Answer:

6

Step-by-step explanation:

I just learned this!! :)

Answer:

it has 6 faces

Step-by-step explanation:

The center of a circle is located at (2, -1). A point on the circle is located at (-3,-1). What is the approximate circumference of the circle?

A16 units
B31 units
C79 units
D100 units

Answers

Answer:

您同性恋

Step-by-step explanation:

Pls help with the circle area and perimeter

Answers

Answer:

circumference = 40.82 m

area = 132.67 m²

Step-by-step explanation:

circumference = diameter x π = 13 x 3.14 = 40.82 m

radius = diameter/2 = 13/2 = 6.5

area = πr² = )3.14)(6.5²) = 132.67 m²

What is 25% of 50= please help

Answers

Answer:

answer 12.5

Step-by-step explanation:

25% of 50 is 12.5 because 50 ÷ 4 = 12.5 Hope that helps!

solve and graph: 7x-6>22
(pls explain your answer, im confused on this)​

Answers

Answer:

x>4

Step-by-step explanation:

Solving an inequality is very similar to solving an equation:

Given: 7x-6>22

Add 6 to both sides: 7x>28

Divide both side by 7: x>4

x>4 means that all x-values that are greater than 4 will work. Therefore you would write an open dot at x=4 on the number line to show that 4 isn't included, and draw an arrow going right to show all possible solutions greater than 4.

what are two factors of 24 that add to be 10? separate each factor by a comma

Answers

6 and 4. The answer has to be 20 characters long in order to post so ignore this part.

Carlos started an exercise program in
January. He kept a record of how many
sit-ups he did each day.
Which correlation value best describes
the data?
Your answer:
O r=-0.9
O r=-0.5
O r= 0
O r=0.5
r = 0.9

Answers

Zero are equal 9.0ifk


Choose All the numbers that round down when rounding to the nearest hundred

Answers

Answer:

3,140, 47,035

Step-by-step explanation:

I would really appreciate if any of you guys can help me on this please and thank you !!

Answers

Answer:

1.

a = 1  b = 3  c = 11

2.

a = 1  b = -7  c = -11

3.

a = 1  b = 4  c = -9

4.

a = 3  b = -1  c = 16

5.

a = 1  b = 0  c = -9

6.

a = 2  b = 5  c = 0

7.

a = -4  b = 0  c = -3

8.

a = 6  b = 0  c = 0

9.

a = -1  b = 1  c = 0

Hope this helps took me a long time to type

b3 + y when
b = 3 and y = 4.5

Answers

Answer:

31.5

explanation if you need it -

b3 + y

when b = 3 and y= 4.5

b x b x b + y

1, substitute the values

3x3x3 + 4.5

27+ 4.5

31.5

9 - (4/9+1/3)
Write and solve a word problem for the expression

Answers

Answer:

9 pizzas total were bought for a party. Maya ate 1/3 of a pizza. John ate 4/9 of the same pizza. How much pizza is left?

Answer: 74/9 or 8.2

Step-by-step explanation:

first add 4/9 and 1/3 since it's in parenthesis

4/9+1/3

they need to have the same denominator, use the LCM (which is 9)

multiply 1/3 by 3 to achieve the LCM

4/9+3/9

add together numerators

7/9

subtract 7/9 from 9

9/1-7/9

get 9 to achieve the LCM (which is 9 again)

multiply 9/1 by 9

81/9 minus 7/9= 74/9

solution of f'(x) = 9x2+2x (-2,2)

Answers

Answer:

f(x) = 3x³ + x² + 22

Step-by-step explanation:

Given

f'(x) = 9x²+2x

To get f(x), we will be integrating the function

f(x) = 9x³/3 + 2x²/2 + C

f(x) = 3x³ + x² + C

at (-2,2)

2 = 3(-2)³ +(-2)² + C

2 = -24 + 4 + C

2 = -20 + C

C = 2+20

C = 22

Get the required function

f(x) = 3x³ + x² + C

f(x) = 3x³ + x² + 22

Marsha deposited ​$5,000 into a savings account 2 years ago. The simple interest rate is 3​%. How much money did Marsha earn in​ interest?

Answers

Answer:

$300

Step-by-step explanation:

(5000)(2)(3/100)

=300

Graph the function f(x) = 2x − 4. Click the intercepts to show the coordinates.

Answers

y-intercept: (0, -4)

x-intercept: (0, 2)

Sorry if this wasn't what you were asking for, I'm not sure if I understood your question correctly. I don't know if you asking just to graph it or if you were asking for the x and y intercepts too, along with the graph. Either way, hope this helped!

Triangle DEF with vértices D(2,1), E(3,5), F(6,2) is reflected acreage the x-axis to make triangle D’E’F

Which rule represents the transformation?
A. (x,y)—>( x,-y)
B. (x,y)—>(-x,y)
C. (x,y)—>(y,-x)
D. (x,y)—>(-y,x)

(Pls help I don’t understand)

Answers

Answer: A

And the answer is literally on top of that question

hey guys may you help me with these questions 1 2 and 3
thank you ​

Answers

Answer:

1a. [tex]\frac{3}{4}[/tex]

1b. [tex]\frac{7}{10}[/tex]

1c. [tex]\frac{3}{10}[/tex]

1d. [tex]\frac{1}{3}[/tex]

2a. [tex]\frac{3}{4}[/tex]

2b. [tex]\frac{1}{5}[/tex]

2c. [tex]\frac{3}{10}[/tex]

2d. [tex]\frac{9}{10}[/tex]

2e. [tex]\frac{1}{20}[/tex]

3. [tex]\frac{1}{8}[/tex]

In most residence, the largest bedroom is considered the Masters Bedroom. Which bedroom would be considered the Masters Bedroom based on area? * bed room 2 bedroom 1

Answers

Answer:

Bedroom 2 will be considered as the Master bedroom.

Step-by-step explanation:

Area of bedroom 1 = Area of room 1 - Area of the closet 1

Area of the room 1 = Length × Width  

                               = (2.5 + 1.4) × (4.3+0.6)

                               = 3.9 × 4.9

                               = 19.11 m²

Area of closet 1 = 1.5 × 0.6

                          = 0.90 m²

Area of bedroom 1 = 19.11 - 0.90

                                = 18.21 m²

Area of bedroom 2 = Area of room 2 - (Area of bathroom + Area of Hall)

Area of room 2 = (3 + 3.1) × (2.5 + 2.4)

                         = 6.1 × 4.9

                         = 29.89 m²

Area of bathroom = 3 × 2.5

                              = 7.5 m²

Area of Hall = 1.2 × 2.4

                    = 2.88 m²

Area of bedroom 2 = 29.89 - (7.5 + 2.88)

                                 = 29.89 - 10.38

                                 = 19.51 m²

Since, area of bedroom 2 is greater than bedroom 1.

Therefore, Bedroom 2 will be considered as the Master bedroom.

Which of the shapes below is a type of quadrilateral? Select all that apply.

A) circle
B) rhombus
C) parallelogram
D) trapezoid

Answers

Parallelogram

Rhombus

Trapezoid

what are the equations and domain/range of each line?

Answers

15,30 is the answer to thois promblem

Help #5-8 easy work thank you

Answers

Answer:

I got you

Step-by-step explanation:

9/10

1/3

3/4

1/2

This table goes through the pairs(51,-65) and (68,-78).What is the yintercept of the line?​

Answers

Answer:

I think the y intercept is (0,-26)

Step-by-step explanation:

Answer:

(0, -26)

Step-by-step explanation:

Find the slope:

m = (-78 + 65)/(68 - 51) = -13 / 17

Use point-slope form to find the equation of the line:

y - (-65) = -13/17(x - 51)y = -13/17x + 39 - 65y = -13/17x - 26

The y-intercept is - 26

How many 1/16 of an inch is in 1 5/8 inch?

Answers

Answer:hei svaret på spørsmålet ditt er c sorry for å kaste bort spørsmålet ditt. Jeg trenger bare poeng jeg er så lei meg

Step-by-step explanation:

A camcorder costing 150 has a markup rate of 35% . Find the markup.

Answers

I'm so sorry I don't know the answer to this question try something else

F = 9/5C + 32 solve for f​

Answers

Answer:

substitute the value for C

Step-by-step explanation:

with that you'd be able to solve for x

Sisters Sharon and Karen enjoy sleeping. Let X represent the number of hours Sharon sleeps each night, and let Y represent the number of hours Karen sleeps each night. The mean of X is 7.9, and the mean of Y is 8.4. Which answer choice correctly calculates and interprets the mean of the sum, S = X + Y?

Mu Subscript s Baseline = 0.5; the mean amount of sleep Sharon and Karen get is 0.5 hours nightly.
Mu Subscript s Baseline = 8.15; the mean amount of sleep Sharon and Karen get is 8.15 hours nightly.
Mu Subscript s Baseline = 8.15; Sharon and Karen can expect to sleep a total of 8.15 hours, on average, nightly.
Mu Subscript s Baseline = 16.3; Sharon and Karen can expect to sleep a total of 16.3 hours, on average, nightly.

Answers

Answer: D

Step-by-step explanation: right on edge :)

[tex]\mu_S[/tex] = 8.15, the mean hours of sleep Sharon and Karen get is 8.15 hours nightly.

What are mean, median, and mode?

The three main methods for identifying the average value of a set of integers are mean, median, and mode.

Adding the numbers together and dividing the result by the total number of numbers in the list yields the arithmetic mean.

The middle value in a list that is arranged from smallest to greatest is called the median.

The value that appears the most frequently on the list is the mode.

Given, Two persons 'X' and 'Y' has mean sleeping hours of 7.9 and 8.4.

Therefore, The mean sleeping hours of both combined is (X + Y)/2 which is,

= (7.9 + 8.4)/2.

= 16.3/2.

= 8.15 hours.

learn more about mean, median, and mode here :

https://brainly.com/question/15323584

#SPJ2

Convert. 19 ft = yd ft

Answers

Answer:

19 ft = 19/3 yd

Step-by-step explanation:

If 3 ft = 1 yd, then 19 ft = 1 yd * 19/3 ft = 19/3 yd

carsonkratsas can u help meh

Answers

Answer:

This might help and hopefully it clears ur doubts:

Step-by-step explanation:

HELP PLS
In the function n = p(m), the __________ is all the possible values of m, and the __________ is all the possible values of n

Answers

Answer:

420

Step-by-step explanation:

420 69

(14 ÷ 2) x 5 + 6

{ 3 x (4 + 1) } ÷ 5


EXPLAIN GIVING BRAINLIEST

Answers

Answer:

25

Step-by-step explanation:

(14÷2)×5+6(3×(4+1))÷5

using BODMAS

7×5+6(3×5)÷5

=7×5+6×15÷5

=35+90÷5

=125÷5

=25

Answer:

1. (14 ÷ 2) x 5 + 6 = 41

2. {3 x (4 + 1)} ÷ 5 = 3

Step-by-step explanation:

PEMDAS. VERY IMPORTANT. THIS ACRONYM WILL HELP YOU WHEN SOLVING MULTI-STEP PROBLEMS. IF YOU DO NOT KNOW IT, SEARCH IT UP. I'LL BE USING PART OF THIS ACRONYM TO SOLVE THIS PROBLEM.

First you solve things in paratheses:

1. (14 ÷ 2) x 5 + 6 -> (7) x 5 + 6

2. {3 x (4 + 1)} ÷ 5 -> {3 x 5} ÷ 5 -> 15 ÷ 5

Then, you multiply or divide next:

1. (7) x 5 + 6 -> 35 + 6

2. 15 ÷ 5 = 3

We already have the answer to number 2, but not number one, so we will keep going. Finally, you subtract or add:

1. 35 + 6 = 41

Now you have your answers. Hope this helps!


Find the inverse of f(x) = -3x.
The inverse is
g(x) =
Graph the function and its inverse

Answers

Inverse is -x/3, -3x is a linear line with a negative slope of 3 (3 up, 1 to the left) that crosses at the origin. -x/3 is also a linear line that crosses at the origin with a slope of -1/3 (1 up, 3 to the left)
Other Questions
If you can answer this, please help ! Harsh restrictions imposed by the Treaty of Versailles High unemployment rates and a worthless currency Lack of agricultural production and hyperinflation All of the above factors led to what type of totalitarian government taking control in which part of the world? What is the value of w in the equation w + 95 = 116 please i need help asap Input a list of positive numbers, terminated by 0, into an array Numbers[]. Then display the array and the largest and smallest number in it. 15 cm30BOAB is a sector of a circle, centre O.The radius of the circle is 15 cm.The angle of the sector is 30.Calculate the area of sector OAB.Leave your answer in its simplest form. A student made a sketch of a potential energy diagram to represent a reaction with a -^HExplain, using complete sentences, why the diagram made by the student is correct or incorrect. Be sure to also explainwhat the values of X and Y represent. identify the three branches of the federal government and summarize the roles of each 20 points is for now Someone please help! Ill give brainliest!! good morning! have a bright and beautiful day! and don't forget to eat and drink water. maybe take a warm bath :) mental health is much more important than school don't push yourself! Read the excerpt from The War of the Worlds. A large portion of the cylinder had been uncovered, though its lower end was still embedded. As soon as Ogilvy saw me among the staring crowd on the edge of the pit he called to me to come down, and asked me if I would mind going over to see Lord Hilton, the lord of the manor. The growing crowd, he said, was becoming a serious impediment to their excavations, especially the boys. Which context clues effectively help indicate the meaning of the word excavations as it is used in the excerpt helpppppppppp pls ill brainlest Which expressions are equivalent to 2.25x ? A rectangular prism is 5 inches long and 10 inches wide. Its volume is 500 cubic inches. What is the height of the rectangular prism? FINANCIAL LITERACY WILL MARK BRAINLIEST PLS HELP ASAP!! What is the process of photosynthesis please dont copy from internet and please explain in 1 paragraph An archiect is building a model of tennis court for a new client. the court is 6 inches wide and 13 inches long an official tennis court is 36 feet wide. what is the length of a tennis court? Yo someone hellp me and if you see this please click! Can someone help me on this?