Answer:
yes I am pretty sure that's correct
An English professor assigns letter grades on a test according to the following scheme. A: Top 13% of scores B: Scores below the top 13% and above the bottom 61% C: Scores below the top 39% and above the bottom 20% D: Scores below the top 80% and above the bottom 10% F: Bottom 10% of scores Scores on the test are normally distributed with a mean of 72.8 and a standard deviation of 7.3. Find the numerical limits for a D grade. Round your answers to the nearest whole number, if necessary.
Solution :
The test is distributed normally with mean of 72.8 and the standard deviation of 7.3
Finding numerical limits for the D grade.
D grade : Scores below the top 80% and above the bottom 10%.
Let the bottom limit for D grade be [tex]$D_1$[/tex] and the top limit for D grade be [tex]$D_2$[/tex].
First find the bottom numerical limit for a D grade is :
[tex]$P(X<D_1)= 0.10$[/tex]
[tex]$P(X\leq D_1)= 0.10$[/tex]
[tex]$P\left(\frac{X-\mu}{\sigma} \leq \frac{D_1-\mu}{\sigma}\right) = 0.10$[/tex]
[tex]$P\left(Z \leq \frac{D_1-72.8}{7.3}\right) = 0.10$[/tex] ..........(1)
From (1)
[tex]$\frac{D_1 - 72.8}{7.3} = -1.28$[/tex]
[tex]$D_1 = -1.28(7.3)+72.8$[/tex]
= 63.45
≈ 64
Now the top numerical limit for D grade :
[tex]$P(X>D_2)= 0.80$[/tex]
[tex]$1-P(X\leq D_2)= 0.80$[/tex]
[tex]$P(X\leq D_2)= 1-0.80$[/tex]
[tex]$P(X\leq D_2)= 0.20$[/tex]
[tex]$P\left(\frac{X-\mu}{\sigma} \leq \frac{D_2-\mu}{\sigma}\right) = 0.20$[/tex]
[tex]$P\left(Z \leq \frac{D_2-72.8}{7.3}\right) = 0.20$[/tex] ..........(2)
From (2)
[tex]$\frac{D_2- 72.8}{7.3} = -0.84$[/tex]
[tex]$D_12= -0.84(7.3)+72.8$[/tex]
= 66.668
≈ 67
Therefore, the numerical limit for a D grade is 64 to 67.
find the value of b in rectangle
what does it mean to be a solution to an inequality
Answer:
Rule 1. Adding/subtracting the same number on both sides.
Example: The inequality x-2>5 has the same answer as the inequality x > 7.
Rule 2. Switching sides and changing the orientation of the inequality sign.
Example: The inequality 5-x> 4 has the same solutions as the inequality 4 < 5 - x.
Done ✔
The graph shows a proportional relationship. Which equation matches the graph.
A. y = 1/5x
B. y = x
C. y = 15x
D. y = 5x
Answer:
D
Step-by-step explanation:
When x = 1, y = 5
When x = 3, y = 15
So, using this, find the slope.
(15 - 5) / (3 - 1) = 10 / 2 = 5
For every x, y increases by 5.
So, y = 5x, or D
Answer:
D
Step-by-step explanation:
5x
Write an
equation and solve.
Ten less than five times a number is 45. the equation is
(x*5)-10=45=equation
im extra so x would be 7
how do u find the angle measure of l
Answer:
The best way to measure an angle is to use a protractor. To do this, you'll start by lining up one ray along the 0-degree line on the protractor. Then, line up the vertex with the midpoint of the protractor. Follow the second ray to determine the angle's measurement to the nearest degree.
Can someone please help me
Answer:
x = 20
y = 12
Step-by-step explanation:
opposite angles are congruent so we can set up this equation:
5x + 29 = 7x - 11
29 = 2x - 11
40 = 2x
x = 20
5(20) + 29 = 129
7(20) - 11 = 129
3y + 15 = 5y - 9
15 = 2y - 9
24 = 2y
y = 12
3(12) + 15 = 51
5(12) - 9 = 51
Use the multiplier method to decrease £56 by 14% show your working
Answer: £46.44
Step-by-step explanation:
£56 × 0.86 or (1 - 0.14)
emmanuel spent 20% on his savings on a new video game that cost 40$. how much was in his savings abount to begin with?
Answer:
He had $200 to begin with.
Which number line best represents the solution to the inequality 7x ≤ 49 ?
Step-by-step explanation:
uedhhhjdjdhdhdddjjdhvdhddbdbddbb
Answer:
A
Step-by-step explanation:
im not 100 % sure hope i am correct
Can you help with this I don’t know how to solve this.
Answer:
[tex]arclength = 13.44 ft[/tex]
Step-by-step explanation:
We are given PS = 28 feet, which is the length of the diameter.
The formula for arc length is [tex]2\pi r\frac{x}{360}[/tex], where x is the degrees.
So, we need to find the radius. We know that the radius is half of the diameter, so:
[tex]\frac{28}{2}=14 ft[/tex]
We also need to find ∠TXS. Since we know the diameter is a line that crosses the center point of the circle, we also know that ∠PXT and ∠TXS add up to 180°. So:
∠PXT + ∠TXS = 180
125 + ∠TXS = 180
∠TXS = 180 - 125
∠TXS = 55°
Now, we can use the arc length formula:
[tex]arclength=2\pi r\frac{x}{360}[/tex]
[tex]arclength=2\pi (14)\frac{55}{360}[/tex]
[tex]arclength=13.43903524...[/tex]
[tex]arclength = 13.44 ft[/tex]
Check my work to make sure! Hope this helps!
Car X traveled 64 miles and consumed 2 gallons of fuel, and Car Y traveled 54 miles and consumed 1.8 gallons of fuel. Which car traveled more miles per gallon?
Answer:
cStep-by-step explanation:
Use the triangle below to answer the following questions:
Joel races bikes. In his city, there are 4 4 lengths of race tracks. The chart shows the race tracks and each track's length in miles. Race Track Length in Miles A 1 4 4 1 B 3 2 2 3 C 1 3 4 1 4 3 D 4 4 4 4 Joel races 3 3 laps in the same lane. The total distance he races is less than 3 3 miles. Which track does Joel race on?
So if Joel raced 3 laps , and the total distance is less then 3 miles then it has to be Track C.
Is the sum of the
angle measures always equal to the
sum of the arc measures
Yes or no ?
Write an equation to represent the total cost y for x days of renting a mid-size car from each of these companies. *
Answer:
Step-by-step explanation:
Hindi ko alm hehe
can someone help me with this I am stuck
Analyze the diagram below and complete the instructions that follow. The diagonals of kite KITE intersect at point P.
A.16 B.26 C.52 D.71
is this right ? if not please help me !
ILL GIVE BRAINLIEST *EXTRA POINTS*..
IM GIVING 40 POINTS !! DONT SKIP :((.
Write an equation in the form y = mx + b
Answer:
y=-2x+8
Step-by-step explanation:
So I select 2 points:
(0,8) and (4,0)
so then I find the slope.
m = [tex]\frac{8-0}{0-4} \\=\frac{8}{-4} \\=\frac{2}{-1} \\=-2[/tex]
m = -2
Then the b (y-intercept) is 8, so equation is:
y=-2x+8
Hoped I helped ([P.S. I love math!)
why is angle 3 congruent to angle 7?
Answer:
they are congruent because they are corresponding angles
Step-by-step explanation:
I have no idea what to do
Answer:
the second is correct
Step-by-step explanation:
choose as brainliest
The ratio of 7/36 to 5/6
Answer:
7 : 30
Step-by-step explanation:
7/36 : 5/6
42 : 180
7 : 30
my question is in the picture
Answer:
x = 1
y = -1
Step-by-step explanation:
-5x + 5y = -10
rewrite the order:
5y = 5x - 10
6x + 5y = 1
rewrite the order:
5y = 1 - 6x
substitute for 5y:
5x - 10 = 1 - 6x
simplify:
11x = 11
x = 1
5y = 1 - 6(1) = -5
y = -1
si en la caja solo cabe media docena de platos, ¿ cuantas cajas serían necesarias para empacar la cantidad inicial de platos ?
Answer:
y cuál es la cantidad inicial de platos?
The manufacturer of a low-calorie dairy drink wishes to compare the taste appeal of a new formula (formula B) with that of the standard formula (formula A). Each of four judges is given three glasses in random order, two containing formula A and the other containing formula B. Each judge is asked to state which glass he or she most enjoyed. Suppose that the two formulas are equally attractive. Let Y be the number of judges stating a preference for the new formula. a Find the probability function for Y . b What is the probability that at least three of the four judges state a preference for the new formula
Answer:
a) [tex]P_y = \frac{4}{y} * \frac{1}{3}^y * \frac{2}{3}^{4-y}[/tex]
b) 0.033
Step-by-step explanation:
Let Y represents the number of judges preferring a formula.
There are total four judges and each judge can select either A or B
n = 4, p = 1/3
a) The probability function is
[tex]P_y = \frac{4}{y} * \frac{1}{3}^y * \frac{2}{3}^{4-y}[/tex]
b)
Substituting the value of y -3 in above equation, we get -
[tex]P_3 = \frac{4}{3} * \frac{1}{3}^3 * \frac{2}{3}^{4-3}\\= \frac{4}{3} * 0.037 * 0.67\\= 0.033[/tex]
PLS HELP ILL GIVE BRAINLIEST
Answer:
y= 2/7
b= 43
Step-by-step explanation:
78.53981... to the one decimal place
math HELPPP MEEEEEEEE
Answer: I HAVE YOUR ANSWER!!!!!
Step-by-step explanation:
51x + 26y + 17
Can someone please help meeeee
Answer:
it will also measure 131 degree
hope it helps
131 degree