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.
Make a equation for the scatter plot line
Answer:
y = -7.2x + 540
Step-by-step explanation:
to find the slope I used the x-and-y intercepts: (0, 540) and (75, 0)
slope = 540/-75 or -7.2
HELP HELP
Tommy rides in a motorboat against a river current for 25 km. Then he returns to his starting point by floating down river on a raft. Tommy travels 10 hours less on the motorboat than on the raft. Find the speed of the river current if the speed of the motorboat in still water is 12 km/h.
The speed of current is [tex]\rm 2 \:km/h[/tex].
What is the relation between distance,speed and time?The relationship between distance, time and speed can be presented as:
[tex]\begin{aligned} \rm Distance &= Speed \times Time\\\\Speed &= \dfrac{\rm Distance}{Time} \\\\\rm Time &= \dfrac{\rm Distance}{\rm Speed} \end[/tex]
Calculations:
Given:
[tex]\begin{aligned} \rm Distance\: traveled\: on\: motorboat &= 25\:km\\\rm Speed\:of\:motorboat\:in\:still\:water &= 12\:km/h \end[/tex]
Let the speed of the current be [tex]\rm x[/tex]
The speed of the boat traveling against the current is [tex]{(12 -\rm x) km/h}[/tex]
Time spent on motorboat is 10 hours less than time spent on raft.
Therefore:
[tex]\rm \dfrac{25km}{x\:km/h} - \dfrac{25km}{(12 - x)km/h} = 10[/tex]
The equation obtained will be:
[tex]\dfrac{25}{\rm x} - \dfrac{25}{(12-\rm x)} - = 10[/tex]
Multiplying both sides of the equation by [tex]\rm x(12 - x )[/tex]
[tex]\begin{aligned} \rm 25(12 - x) - 25x &= 10\times \rm x(12 - x)\\\\300 - 25x - 25x &= 120x - 10x^2\\\\300 - 50x &= 120x - 10x^2\\\\10x^2 - 120x - 50x + 300 &= 0\\\\10x^2 - 170x +300 &= 0\end[/tex]
Dividing the equation by 10
[tex]\rm x^2 - 17x + 30 = 0[/tex]
On factoring the equation,
[tex]\rm =x^2 - 2x -15x + 30 = 0\\\\=x(x - 2) -15(x - 2)\\\\=(x - 2)(x - 15)[/tex]
The values of x is 2 and 15.
Since speed of current i.e [tex](12 -\rm x)km/h[/tex] cannot be negative, [tex]\rm x = 2[/tex] is the only acceptable value.
Therefore the speed of current is 2 km/h.
Learn more about the topic here:
https://brainly.com/question/2292310
Write an expression for the sequence of operations described below.
10 plus the quotient of 8 and u
Do not simplify any part of the expression.
Answer:
[tex]10 + \frac{8}{u}[/tex]
Step-by-step explanation:
Given
10 [tex]plus[/tex] the [tex]quotient[/tex]of 8 and u
Required
Represent as a mathematical expression
Square out the operators
10 [[tex]plus[/tex]] the [[tex]quotient[/tex]] of 8 and u
[tex]plus => +[/tex]
[tex]quotient => /[/tex]
Replace the operators with their signs
[tex]10 + \frac{8}{u}[/tex]
Help please someone A, B, or C ?
Answer:
it got to be b 2:2
please help i will give brainliest
Is this right? Please help
Answer: I believe that is correct! good jobbb
Step-by-step explanation:
the tax on a purchase of $20 is $2.80. How much tax will there be on a purchase of $45.50?
Answer:
$6.37
Step-by-step explanation:
You divide 2.80 by 20 to find the percentage of tax then you simply multiply your percentange by the cost. In this problem the tax was 14% or .14, so you multiply .14 by 45.50 to find the amount of tax on the purchase
Don operates a small craft store in which he sells other peoples crafts. He takes a 45% commission from the sales of all crafts. If he earns $958.00 Commission last week, how much did he sell?
Answer:
2,128
Step-by-step explanation:
958=45/100 x
958= 0.45* x
x=958/0.45
x=2,128 approximately
Hope that helps!
Can someone please help!!!
Answer:
its the 3rd one
Step-by-step explanation:
1
Cindy has a 4-shelf bookcase in which she wants to place baskets. Each basket takes up of one shelf as shown
4
Cindy wants to place as many baskets on the shelves as possible. How many baskets can Cindy place on the 4 shelves?
Previous
Answer:
obviously 16 books....
You cannot use critical numbers and test intervals to solve quadratic and
rational inequalities.
True
False
Answer:
False
Step-by-step explanation:
You can use test intervals and critical numbers to solve quadratic and rational inequalities.
Factor the algebraic expression.
12a+9
Can someone please help me answer this is a test and I need to hurry
Answer:
27
Step-by-step explanation:
The second term in a geometric sequence is 12. The fourth term in the same sequence is 4/3 what is the common ratio in this sequence
Answer:
The common ratio in this sequence is 6:2 or 4:3
Step-by-step explanation:
hopes this heklps
PLS HELPPP
What value of x would make the following relation a function?
{(-3,-2),(2,3),(3,2),(x,2)}
A. -3
B. -2
C. 2
D. 3
Which equation represents the function f(x) = (1.6)x after it has been translated 5 units up and 9 units to the right?
Answer:
It's C. g(x) = (1.6)x − 9 + 5
Step-by-step explanation: hope it helps ^w^
What percent of $80 is $20
Answer: $20$20 is $25\%$25% of $80$80.
Step-by-step explanation:
25
Which of the following World Record times from Track and Field is least
precise?
A. 47.6 seconds (400 m -Women)
B. 43.18 seconds (400 m - Men)
C. 21.34 seconds (200 m-Women)
D. 9.79 seconds (100 m - Men)
Answer:
THE ANSWER SHOULD BE D OR B
Step-by-step explanation:
I DON'T KNOW
what is the square root of -20
Answer:
4.47213595
Simplify in the tenths place and get 4.47
Step-by-step explanation:
(9x10^10) - (4x10^10)
Answer: 50000000000 is your answer.
Step-by-step explanation:
g Suppose the population 10-year cumulative incidence of prostate cancer among 70-year old men is 0.06. Further, suppose 260 men without prostate cancer, aged 50 years were randomly sampled and 13 of them developed prostate cancer within 10 years. Is there evidence at the 0.05 significance level to conclude that the cumulative incidence of prostate cancer among 50-year old men differs from that of 70-year old men
Answer:
There is not enough statistical evidence to conclude that the cumulative incidence of prostrate cancer among 50-year old men differs from that of 70-year old men
Step-by-step explanation:
The population 10 year cumulative incidence of prostrate cancer among 70 year old men, p = 0.06
The number of 50 year old men in the sample, n = 260 men
The number of the sampled men that developed prostrate cancer = 13 men
The significance level, α = 0.05
Let the null hypothesis, H₀: [tex]\hat{p}[/tex] = p
The alternative hypothesis, Hₐ: [tex]\hat{p}[/tex] ≠ p
The standard score, [tex]z_{\alpha /2}[/tex] = 1.96
The test statistic, 'z', is given as follows;
[tex]z=\dfrac{\hat{p}-p}{\sqrt{\dfrac{p \cdot q}{n}}}[/tex]
[tex]\hat{p}[/tex] = 13/260 = 0.05
q = 1 - p = 1 - 0.06 = 0.94
[tex]Therefore, \ z=\dfrac{0.05-0.06}{\sqrt{\dfrac{0.06 \times 0.94}{260}}} = \dfrac{\sqrt{9165} }{141} \approx -0.68[/tex]
From the z-table, we find the p-value as follows;
P(z ≈ -0.68) = 0.24825
Therefore, given that the p-value, 0.24825 is larger than the significance level, α/2 = 0.025, we fail to reject the null hypothesis, and therefore, there is not enough statistical evidence to conclude that the cumulative incidence of prostrate cancer among 50-year old men differs from that of 70-year old men
(x2 – 3x + 2)/(4x - 16)
Answer:
Pretty sure it's x^2−3x+2/4x-16
Step-by-step explanation:
Given that A and I are the centers of the congruent circles shown below, compare the quantity in column A with the quantity in column B. Choose the best answer. The quantity in column A is greater. The quantity in column B is greater. The two quantities are equal. The relationship cannot be determined from the information given.
Answer: The two quantities are equal
Step-by-step explanation:
Edge2021
C. The two quantities are equal
Step-by-step explanation:
Edge 2020 2021
PLEASE HELP MEE it’s urgent
Answer:
positive9/50
Step-by-step explanation:
9/50
Answer:
the answer is 9/50 (fraction).
Step-by-step explanation:
hope this helped!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Suppose two angles in a coordinate plane, one measuring 80° and the other measuring 160°, were both rotated 180° about the origin and then translated 40 units down. Which of these would be a measure of
one of the resulting angles? Select all that apply.
160°
340°
80°
40°
120°
260°
Answer:120 and 160
Step-by-step explanation:
i did it
80° and 160° could be a measure of one of the resulting angles.
What are angles?Two rays intersect to form a angle. The point of intersection is called the vertex point.
Given is that two angles in a coordinate plane, one measuring 80° and the other measuring 160°, were both rotated 180° about the origin and then translated 40 units down.
There is no effect of rotation and translations on the angles. Hence, we can say that 80° and 160° could be a measure of one of the resulting angles.
Therefore, 80° and 160° could be a measure of one of the resulting angles.
To solve more questions on angles visit the link below-
brainly.com/question/1041084
#SPJ6
pls answer this-.....
AnswerS:
Let A be the surface area, b the base, h the height;
h₁=8.4 cm
h₂=7.8 cm
b= 9 cm
A= 3(1/2bh₁)+1/2 bh₂
A=3(1/2(9)(8.4))+1/2 (9)(7.8)
A= 148.5 cm³
Answer:
Step-by-step explanation:
The figure given above is a square pyramid, having a square base and 4 triangular faces on the sides that are of the same dimensions.
Surface area of the square pyramid is given as:
Where,
B.A = Base Area of the pyramid = 9*9 = 81 in²
P = perimeter of the base = 4(9) = 36 in
L = slant height of pyramid = 9.2 in
Plug in the values into the given formula to find the surface are
what shape can be formed from the following net?
Answer:
A Triangular Prism
Hope that helps!
Step-by-step explanation:
Answer: Triage
Step-by-step explanation:
The matrix is used to solve a problem. Which of the following would be a solution to the problem?
Answer:
(1,5)
Step-by-step explanation:
Hope this is right.
Answer:
It's (1,0)
Step-by-step explanation:
I got it right on the quiz
The factors of a polynomial are (x + 3x - 2)(x+ 7) The polynomial has been graphed. How do the zeros relate to the factors?
A. The zero is the sum of the numbers inside the parenthesis
B. There is no relationship between the factors and the zeros.
C. The number inside each parenthesis are the zeros of the equation.
D. If you set each factor equal to 0 and solved you would get the zeros.
Answer:
its C I am pretty sure about it
Answer:
D: If you set each factor equal to 0 and solved you would get the zeros.
Step-by-step explanation:
Completed it on PL also because 0 should be base
Use each number in the box once to complete the division
5÷6,206
Answer:
i believe it is 1,241.2
Step-by-step explanation:
well you use long division.