A psychology professor assigns letter grades on a test according to the following scheme. A: Top 9% of scores B: Scores below the top 9% and above the bottom 56% C: Scores below the top 44% and above the bottom 20% D: Scores below the top 80% and above the bottom 6% F: Bottom 6% of scores Scores on the test are normally distributed with a mean of 79.3 and a standard deviation of 8.4. Find the numerical limits for a D grade. Round your answers to the nearest whole number, if necessary.
Answer:
You get a D if you have a grade between 66 and 72.
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 zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Scores on the test are normally distributed with a mean of 79.3 and a standard deviation of 8.4.
This means that [tex]\mu = 79.3, \sigma = 8.4[/tex]
D: Scores below the top 80% and above the bottom 6%
So between the 6th and the 20th percentile.
6th percentile:
X when Z has a pvalue of 0.06. So X when Z = -1.555.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.555 = \frac{X - 79.3}{8.4}[/tex]
[tex]X - 79.3 = -1.555*8.4[/tex]
[tex]X = 66.2[/tex]
Rounds to 66
20th percentile:
X when Z has a pvalue of 0.2. So X when Z = -0.84.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-0.84 = \frac{X - 79.3}{8.4}[/tex]
[tex]X - 79.3 = -0.84*8.4[/tex]
[tex]X = 72.2[/tex]
Rounds to 72
You get a D if you have a grade between 66 and 72.
y=24-4x function table
Answer:
here
Step-by-step explanation:
Answer:
Step-by-step explanation:
The slope of a linear function is 1/5. For every rise of 5 units, what is the run?
Answer:
for every rise of 1 the run would be 25
Is 6 right?? Please help
Answer:
yes, it should be
Step-by-step explanation:
can somebody help me?
please help me find the missing side !
Answer:
x=14 and y=7
Step-by-step explanation:
This is a 30-60-90 triangle
So in terms of x it would be [tex]x-x\sqrt{3} -2x[/tex]
If across the 60 is [tex]7\sqrt{3}[/tex] then y would be 7 which is across the 30 degrees
And x would be 14 because 2(7)=14
.nooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
Answer: What is this free?
Answer:
yes
Step-by-step explanation:
yes+yes(no-no)
=yes
Value of ratio 3/4 to 2
Answer:
3/8 or 0.375
Step-by-step explanation:
0.75/2 = 3/8
Is 2 a solution of 4z + 12 = 4? Complete the statement.
Answer:
No im pretty sure its not a solution.
Step-by-step explanation:
See if “z” is 2 than the answer to the solution would be 20
Answer:
The solution is -2
Step-by-step explanation:
4z + 12 = 4
Subtract 12 on each side (4z + 12 - 12 = 4 - 12)
4z = -8
Divide 4 on each side (4z / 4 = -8 / 4)
z = -2
Find the area of each. Use pi = 3.14
Martina is currently 18 years older than her cousin Joey. In 5 years she will be 3 times as old as Joey . Use this information to answer the following questions.
If you let x represent Joey's current age, what expression can you use to represent Martina's? PLEASE HELP
current age?
Answer:
The age of Joey is 4 years and
The age of Martina is 22 years .
Step-by-step explanation:
Given as :
Martina is 18 years older than her Joey
In 5 years, Martina will be three times older than Joey
Let The age of Martina = M years
And The age of Joey = J years
Now, According to questions
M = J + 18 ........1
(M+5) = 3 × (J+5)
Or, M + 5 = 3 J + 15
Or, M - 3 J = 15 - 5
∴ M - 3 J = 10 ..........2
Solving eq 1 and 2
Put the value of M from eq 1 into eq 2
So, (J + 18) - 3 J = 10
Or, J - 3 J = 10 - 18
Or, - 2 J = - 8
∴ J =
i.e J = 4 years
So, The age of Joey = J = 4 years
Now, Put the value of J in eq 1
So, M = J + 18
Or, M = 4 + 18
∴ M = 22 years
So, The age of Martina = M = 22 years
Hence,The age of Joey is 4 years and The age of Martina is 22 years . Answer
In ΔJKL, j = 520 inches, k = 730 inches and l=640 inches. Find the measure of ∠K to the nearest degree.
Answer:
It’s 56.7
Step-by-step explanation:
Fudisks
Who can help me with this question problem
Answer:
use the formula and evaluate the givens
Step-by-step explanation:
336=(14/11)^2 * 22/7*h
336=196/121 * 22/7h
336= 4312/847h
336= 5.09h
h=66
The receipt below shows the money, in dollars, spent by a customer at the good groceries stores
I Question 7 (2 of 13)
Find area of shaded region. Round to the nearest tenth.
50 cm
radius: 20 cm
80 cm
Enter your answer by clicking the bubbles.
what is the measurement of jkl
Answer:
The angles combined together are 200, so you will have to subtract the difference of 200 and 180 from the combined angles. The angle of line JKL is 160 degrees.
Step-by-step explanation:
Please mark as brainliest!
Answer:
The measure of angle JKL is 97 degrees.
Step-by-step explanation:
Does the table represent an exponential function? Explain why or why not.
(3,-10 ), (4,-7 ), (5,-4), (6,-1), (7,2),(8,5)
Answer:
No, it does not.
Step-by-step explanation:
It's a linear function, with a slope of -3 (down 3 for every new X as you move right)
The Property where if the order of addends changes, the sum stays the change
Which number is not a factor of 42?
2 3. 4 7
Answer:
3
by using divisibility test
Answer: Its 3
Step-by-step explanation: This is because 42 can be divided by 2 4 and 7 and still be a whole number but when you divide 3 by 42 you get 10.5
Hope this helps and have a nice day
-2y + 4 > 10
solve the inequality
Step-by-step explanation:
-2y+4>10
subtract 4 from both sides
-2y+4-4>10-4
-2y>6
divide both sides by two
-2/2y>6/2
-1y>3
if negative y is greater than three than you have to multiply both sides of the equation by -1
y>-3 if you put that back into the earlier equation it is impossible.
so we have to switch the signs to < or less than
y<-3
Hope that helps:)
Help please !!!! This is really hard
Answer:
Option -c :5^ -12 . 2^ 40
Step-by-step explanation:
( 5^6 . 2^8 )( 5^-2 . 2^5 )
( 5^6 . 5^-2 ) ( 2^8 . 2^5 )
5^ -12 . 2^ 40
Option -c : 5^ -12 . 2^ 40
I hope im right!!
The length of a rectangle is 20 inches less than twice the width. The perimeter of the rectangle is 86 inches. Find the dimensions of the rectangle.
Answer:
length=22
width=21
Step-by-step explanation:
let, length be x and width be y.
x=2y-20
2(x+y)=86
or, 2(2y-20+y)=86
or, 2(3y-20)=86
or, 6y-40=86
or, 6y= 126
or, y= 126/6
y= 21
x= 2×21-20 = 42-20 =22
What is the formula for calculating Cone?
Help please. Monica estimates the recipe makes about 5 cups of fruit salad. which example describes whether Monica estimates is reasonable?
Not reasonable. Four fractions cannot equal more than 4 cups.
B
Not reasonable. The whole numbers add up to 3 so the total sum cannot be 5 cups.
C
Reasonable. The grapes and apples is about 2 cups and pears and oranges is exactly 3 cups.
D
Reasonable. The pears and apples is about 3 cups and the grapes and oranges is exactly 2 cups.
Answer:
A.
Step-by-step explanation:
Not reasonable, Why did you put that as your answer?
The whole numbers add up to more then 4 cups.
Y - 5= - (5 - y)
Does it have a solution?
Answer:
infanite
Step-by-step explanation:
Enter the product as a mixed number
9514 1404 393
Answer:
10 1/5
Step-by-step explanation:
3 × 3 2/5 = 3(3) +3(2/5) = 9 +6/5 = 9 + 1 1/5
= 10 1/5
Use the table to write a linear function that relates y to I.
X
-2
0
2
4
y
-7
- 7 - 7
- 7
=
10
Answer:
y = -7
Step-by-step explanation:
✔️Find the slope (m) using any two pairs of values, say (0, -7) and (2, -7):
Slope (m) = ∆y/∆x = (-7 -(-7))/(2 - 0) = 0/2 = 0
Slope (m) = 0
✔️Find y-intercept (b):
y-intercept is the value of y when x = 0. From the table, when x = 0, y = -7.
Therefore, y-intercept (b) = -7
✔️ Substitute m = 0 and b = -7 into y = mx + b (slope-intercept form):
y = 0(x) + (-7)
y = -7
The equation y = 10x shows how the
cost relates to the number of hours.
How much does it cost to rent a canoe
for 8 hours?
11 and 3/8 pounds of cat food were donated to the shelter
If the area of a rectangle is (15x2 - 16x - 15) square feet, and its length is (3x - 5) feet, find its width
Answer:
255
Step-by-step explanation:
(15x2 - 16x - 15) = 270
(3- 5) = -15
270
- -15
= 255
The breadth of the rectangle is (-5x-3).
Area of rectangleThe area of a rectangle is given as the product of its length to its breadth.
[tex]\rm{Area\ of\ Rectangle = Length \times breadth\\[/tex]
Given to usarea of a rectangle = (15x2 - 16x - 15)
length = (3x - 5)
Width[tex]Area\ of\ Rectangle = Length \times breadth\\(15x^2-16x-15)=(3x-5)\times breadth\\\\(3x-5)\times breadth=(15x^2-16x-15)\\\\breadth = \dfrac{(15x^2-16x-15)}{(3x-5)}\\\\breadth = (-5x-3)[/tex]
Hence, the breadth of the rectangle is (-5x-3).
Learn more about Rectangles:
https://brainly.com/question/10046743