Answer:
can you type it in english pls, thank you
Let X be the percentage score on a college-entrance exam for students who did not participate in an exam-preparation seminar. X is modeled by a uniform distribution on [a,100]. Let Y be the percentage score on a college-entrance exam for students who did participate in an exam-preparation seminar. Y is modeled by a uniform distribution on [1.25a,100]. It is given that E[X^2] = 19,600/3.Calculate the 80th percentile of Y. A. 80 B. 85 С. 90 D. 92 E. 95
Answer:
E. 95
Step-by-step explanation:
[tex]\text{Given that:} \\ \\ X \sim U(a,100) \\ \\ fx(x) = \dfrac{1}{100-a} \\ \\ E[X^2] = \int _x f_x (x) \ dx \\ \\ \implies \int^{100}_{a} \dfrac{x^2}{100-a}dx \\ \\ =\dfrac{100^3-a^3}{3(100-a)} \\ \\ =\dfrac{100^2+100a+a^2}{3} \\ \\ E[X^2] = \dfrac{19600}{3}=\dfrac{100^2+100a+a^2}{3} \\ \\\implies a^2 +100a+10000=19600 \\ \\ \implies a^2 +100a -9600 = 0 \\ \\ \implies a = \dfrac{-100 \pm \sqrt{100^2 -4(-9600)} }{2} \\ \\=\dfrac{-100 \pm \sqrt{48400}} {2} \\ \\ = \dfrac{-100 \pm 220}{2} \\= 60 \ OR \ 160[/tex]
[tex]\text{SInce X is a percentage score on an exam }\ P(X \ge 0) = 1 \text{which means } \ a = 60\\ \\Y \sim U (1.25a,100) = U(75,100)\\ \\ f_y(y) = \dfrac{1}{100-75} = \dfrac{1}{25} \\ \\ \text{Let assume the 80th percentile of Y be} \ y_{80} } \\ \\ \\Then; \ P(Y \le y_{80}) =80\% \implies \int^{y_{80}}_{75} \ f_Y (y) \ dy = 0.8 \\ \\ \implies \int^{y_{80}}_{75}\dfrac{1}{25} \ dy = 0.8 \\ \\ \implies \dfrac{y_{80}-75}{25}= 0.8 \\ \\ \implies y_{80} = 95[/tex]
What number would make this problem many solutions?
Infinity many solutions :
10x+ ___ =2(5x+7)
2
5
7
14
17
20
Answer:
14
.........................
Answer:
14
Step-by-step explanation:
Distribute the right hand side of the equation to get 10x +14. To have infinitely many solutions, the left hand side would be the same so the answer is 14.
A rectangular poster has an area of 38 square feet. It is 4 3/4 feet wide at its base. What is the height of the poster
Answer: The height is 8
Step-by-step explanation:
4.75 x 8 = 32
Find two numbers whose sum is 9 and their difference is 60.
Smaller-
Large number-
Answer:
Step-by-step explanation:
x+y = 9
x-y = 60
-----------
2x = 69
x = 34.5
y = 9-x = -25.5
smaller number: -25.5
larger number: 34.5
Zorion’s mother helped him plan a budget. He had to put half of his money into savings. Whatever was left he split evenly into 3 categories: entertainment, snacks, and clothes. Which table correctly shows the budgeted amounts in each category if Zorion got $60 for selling his bike?
Answer:
it's the first one because it is split as the paragraph said it should
A ramp is elevated to a height of 27 inches from the base. The horizontal distance between the lower end of the ramp and the base is 69 inches, as shown in the figure. What is the length of the ramp?
Answer:
74.09453421...
Step-by-step explanation:
Pythagorean Theorem
help someone plz I'll give brainlest
Answer:
like with the whole page?? cause if so i got this KINDA
Step-by-step explanation:
the first one (2/9+2/9) = 4/9
the second one (1/4+2/4)=3/4
the third one (3/8+5/8)=1 whole or 8/8
i cant see the last one so ill skip to the bottom row
the first one (2/5-1/5)=1/5
(9/12-4/12)=5/12
(4/10-2/10)= 2/10
and ill give someone else a shot with the rest of the questions but yw
this is pretty simple but hit me up if you ever need more help
=D
Answer:
Section 1
Adding and Subtracting- just add/subtract (depending on what the question is asking you) the numerators (top number), don't do anything to the denominators (bottom numbers)
Step-by-step explanation:
Section 1
Adding and Subtracting- just add/subtract (depending on what the question is asking you) the numerators (top number), don't do anything to the denominators (bottom numbers)
Section 2
Make the denominators (bottom numbers) the same, then add or subtract the numerators. To make the denominators same, apply a common factor to the bottom number.
Section 3
Multiply the top numbers and bottom numbers to get the answer.
Section 4
Use KCF: Keep, Change and Flip. Keep the first fraction the same, then change the division sign to a multiplication and finally flip the last fraction, then multiply the two fractions.
A catering company charges a flat fee of 120$ to cater an event...
4. Jean and Mark are going to fill a pool with 2 different sized hoses. Jean can fill the pool in 4 hours, while Mark can complete it in 6 hours. Their supervisor thinks that the job will take 5 hours to
complete if they work together. Explain each step in solving this equation, and determine if the supervisor is correct or not.
Answer:
2.4 hours.
Step-by-step explanation:
Remark
The supervisor is not quite correct. The correct answer must be lower than the lowest number, otherwise you are taking out what the person with the narrower hose must be taking out what the other person is putting in.
Equation
Let x = the amount of time needed for him to fill the pool
Let y = the amount of time needed for the second person to fill the pool
Let z = the amount of time needed for both to fill the pool.
1/x + 1/ y = 1/z
1/4 + 1/6 = 1/z The common denominator is 12
3/12 + 2/12 = 1/z
5/12 = 1/z Cross multiply
5z = 12 * 1 Divide by 5
z = 12/5
z = 2 2/5
z = 2.4 hours
Each of the following hypothetical data sets represents some repeated weighings of a standard weight that is known to have a mass of 100 g. Assume that the readings are a random sample from a population that follows the normal curve. Perform a t test to see whether the scale is properly calibrated, if possible. If impossible, explain why.
a. 100.02.99.98,100.03
b. 100.01
Answer:
b
Step-by-step explanation:
Please help soon!! I will give brainliest to the first correct answer!
Answer:
1(left) goes with 1
2(left) goes with 3
3(left) goes with 2
4(left) goes with 4
Step-by-step explanation:
2(5+6) = 22
3(5+3) = 24
2(4+5) = 18
2(3+2) = 10
10 + 12 = 22
8+ 10 = 18
15 + 9 = 24
6 + 4 = 10
1(left) goes with 1
2(left) goes with 3
3(left) goes with 2
4(left) goes with 4
Answer:
10 + 12 = 2(5+6) . 10+12=22, 5+6 = 11, 11×2 =22 or 2× (5+6) = 22.
8+10= 2(4+5) , 8+10=18. 2 × (4+5) = 18, 4+5=9, 9×2=18.
15+9= 3(5+3) , 15+9=24, 5+3=8, 8×3 =24 or 3× (5+3)
6+4= 2(3+2), 6+4=10, 3+2 = 5 , 5×2 =10
help me plz branniest to whoever is right
Answer:
x= -7, x=8
Step-by-step explanation:
factoring method..
f (x) = - x² + 12x - 20
= - x² + 10x + 2x - 20
= - x( x - 10 ) + 2( x - 10 )
= ( x - 10 ) ( -x + 2 )
=> x = 10, x = 2
x over 8 = 10?
i just need to solve for x
What is the probability that a data value in a normal distribution is between a
z-score of -0.37 and a z-score of 1.22? Round your answer to the nearest
tenth of a percent.
A. 54.3%
B. 52.3%
C. 51.3%
D. 53.3%
Answer:
53.3%
Step-by-step explanation:
It's the correct answer that's why
Is the ratios 2.5 : 8 and 7.5 : 24 are they equivalent?
Answer:
Yes, they are equivalent.
Step-by-step explanation:
To get from 2.5 : 8 to 7.5 : 24, you have to multiply by both sides by 3.
So they are equivalent.
WILL MARK BRANILIEST PLZ HELP
Type the correct answer in the box. Use numerals instead of words, and round your answer to the nearest whole number.
Meghan flipped a quarter and rolled a standard six-sided die.
The probability that the coin landed on heads and the die landed on an even number is __%.
Answer:
25%
Step-by-step explanation:
Multiply the two probabilities.
P(heads)*P(even) = 1/2*1/2 = 1/4
1/4 = 25%
Please help me ?????!! Anyone help me ?!!!
HELP PLEASE DUE IN 4 MINUTES
Step-by-step explanation:
can somebody help me with math I have 3 more questions OWO:
If Jeff drives 200 miles per hour in his race car, and this relationship is graphed, which ordered pair would not be on the graph?
1. (2, 400)
2. (0, 0)
3. (8, 1,600)
4. (5, 1,200)
please don’t steal all my points UwU :( :’)
The ordered pair would not be on the graph is (5, 1200)
The correct option is (4).
What is Equation?Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides. LHS = RHS is a common mathematical formula.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
Given:
If Jeff drives 200 miles per hour in his race car.
So, if we denote the distance by y and time by x then relation is
y = 200x
For x = 0
y=0
and, x= 2
y= 400
and, x= 8
y= 1600
and, x= 5
y = 1000
Hence, the point not on the graph is (5, 1200)
Learn more about Equation here:
https://brainly.com/question/29657983
#SPJ2
1. Quadrilateral ABCD has AB = x+3 and CD= 5x –7. What is the length of x
for which the quadrilateral is a parallelogram?
Answer:
x = 2.5
Step-by-step explanation:
since it's a parallelogram, AB = CD so:
x + 3 = 5x - 7
subtract x from each side of the equation:
3 = 4x - 7
add 7 to each side:
4x = 10
divide both sides by 4:
x = 2.5
1. The diameter of a circle is 8. what is the radius?
Answer:
Radius = 4
Step-by-step explanation:
r = d/2
r = 8/2
r = 4
Answer:
4
Step-by-step explanation:
The diameter of a circle is the length of a straight line from two opposite points on the circle. The radius is the length of a straight line from the middle to a point on the circle. This means that the diameter must be double the radius. So to find the radius, divide the diameter by 2. Since 8/2=4, the radius is 4.
Find the probability of being dealt a "jacks over aces" full house (three jacks and two aces). (Round your answer to six decimal places.)
Answer:
1.500000
Step-by-step explanation:
jacks over aces
3÷2
=1.5
correct to six decimal places
1.500000
what is 2/5 x 5/6
i need the answer in 3 minutes
1/3
...............
.
...........
Answer:
1/3
Step-by-step explanation:
Which ordered pair is a solution of the equation?
-7x+3y=2
Choose 1 answer:
(Choice A)
A
Only (1,3)
(Choice B)
B
Only (−2,−4)
(Choice C)
C
Both (1,3)(-2,-4)
(Choice D)
D
Neither
A bag contains: • 2 white marbles • 3 brown marbles • 4 purple marbles • 6 orange marbles A marble will be drawn from the bag and replaced 75 times. What is a reasonable prediction for the number of times a brown or purple marble will be drawn?
Answer:
45
Step-by-step explanation:
There are 14 total marbles. The probability of drawing a yellow marble on the first draw is 3/14. Given replacement, the probability on the second draw is the same as on the first draw, so the probability of black marble on the second draw is 6/14. The probability of drawing first a yellow marble then a black marble is 3/14 * 6/14 = 18/196.
Answer:
35
Step-by-step explanation:
sorry, i dont have an explanation for this i just guessed and it was right, here u go :)
HELPPPPPPPPP MATH PLEASE
Answer: 14
Step-by-step explanation:
Answer:
12 units^2
Step-by-step explanation:
The triangle on the left has an area of 2, the square has an area of 4 and the triangle on the right has an area of 6.
Add these up to get 2+4+6 = 12
A triangle has side lengths of 11 cm and 6 cm. Which could be the value of the third side, 21 cm or 14 cm? Is it 14 or 21?
Answer:
14
Step-by-step explanation:
As long as two sides of a triangle added together are larger than the third side, it is an accurate triangle!
I'm begging for help. This is the third time i've posted this, and I'm so confused. I don't understand how to use this chart to get the fractional inches. I really need help, please help. :(
Answer:
yes, I am pretty sure you do .122 as 1/8 and you keep doing that. I am pretty sure :)
Step-by-step explanation:
Also could you please give me brainliest?
Answer:
was popping. Free points right
Step-by-step explanation:
I don’t know what to do
Answer:
i think it would be the first one i am not 100% sure just a gues
Step-by-step explanation:
I NEED HELP FAST! Which of the following sets of numbers could not represent the three sides of a triangle?
Answer:
Im pretty sure that 12, 18, and 29 would be the answer to your question.
Step-by-step explanation: