Given: The number of minutes that it takes students to fill out an online survey has an approximately normal distribution with mean 11 minutes and standard deviation 2.5 minutes.
a. About 34.46% of students take more than 12 minutes to fill out the survey.
b. About 17.3% of students take between 9 and 14 minutes to fill out the survey.
c. 75% of students fill out the survey in less than 12.675 minutes.
d. 80% of students will be within 1.28 standard deviations of the mean.
a. In this problem, we have μ=11 and σ=2.5.
We need to find out the percent of students who take more than 12 minutes to fill out the survey.
Using z-score formula, we get
z=(x−μ)/σ
=(12−11)/2.5
=0.4
Now we can use a standard normal distribution table to find the percentage of students taking more than 12 minutes. Looking up the z-score of 0.4, we get the probability of 0.3446 or 34.46% approximately.
Therefore, about 34.46% of students take more than 12 minutes to fill out the survey.
b. Now we need to find out the percentage of students who take between 9 and 14 minutes to fill out the survey.
Using z-score formula for the lower and upper limits, we get
z_(lower)=(9−11)/2.5
=−0.8
z_(upper)=(14−11)/2.5
=1.2
Now we can use a standard normal distribution table to find the percentage of students taking between 9 and 14 minutes. Looking up the z-score of -0.8 and 1.2, we get the probabilities of 0.2119 and 0.3849 respectively.
The difference between these probabilities gives us the answer:0.3849−0.2119=0.173.
Therefore, about 17.3% of students take between 9 and 14 minutes to fill out the survey.
c. Now we need to find out the time taken by 75% of students to fill out the survey.
Using a standard normal distribution table, we can find the z-score that corresponds to the probability of 0.75.
This is approximately 0.67. Using the z-score formula, we can find out the time taken by 75% of students.
z=0.67
=(x−11)/2.5
Solving for x, we get x=12.675.
Therefore, 75% of students fill out the survey in less than 12.675 minutes.
d. Finally, we need to find out how many standard deviations away from the mean do we have to go to capture 80% of the students.
Using a standard normal distribution table, we can find the z-score that corresponds to the probability of 0.9. This is approximately 1.28.
Using the z-score formula, we can find out the deviation from the mean that corresponds to this z-score.
1.28=(x−11)/2.5
Solving for x, we get x=14.2.
Therefore, the deviation from the mean is 14.2−11=3.2 minutes.
Since 80% of the students lie within this deviation, we can say that 80% of students will be within 3.2/2.5=1.28 standard deviations of the mean.
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Is j+j+j+j and j with the power of four equivalent?
Answer:
No, they are not equivalent.
Step-by-step explanation:
j + j + j + j = 4j
j^4
Let's say j = 2
4j = 8
j^4 = 16
Answer:
NO
Step-by-step explanation:
j+j+j+j
remember multiplication is repeated addition!
j+j+j+j = 4j
THIS IS DIFFERENT! powers are repeated MULTIPLICATION.
j^4 = j to the power of 4 = j * j * j * j, NOT j+j+j+j !!!!!
Determine the equation of the circle graphed below
The equation of the circle graphed below is (x - 2)² + (y + 3)² = 25.
To determine the equation of a circle, we need the center and the radius of the circle. In the graph below, the center appears to be at (2, -3) and the radius appears to be 5.
Therefore, we can use the standard equation of a circle,
which is (x - h)² + (y - k)² = r²,
where (h, k) is the center of the circle and r is the radius.
Substituting the values of the center and radius, we obtain the equation of the circle as follows:(x - 2)² + (y + 3)² = 25
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$17.99 with an 11.25% tax
Answer:
it's 2.0
hope that helps
у
80
The graph of quadratic function
is shown on the grid.
What is a solution to r(x) = 0?
60
40
A -50
20
B 4
х
-4
4
8
12
- 16 -12 -8
16
C 14
-20
D-60
vo
-60
-80
Answer:
C 14
Step-by-step explanation:
Alyssa walked 1.34 fewer miles than Emily. Alyssa walked 7.45 miles. How many miles did Emily walk?
If Ann travels 50 meters North, 200 meters East and 150 meters South, what is her total distance travelled ? A. 150 meters B.400 meters C. 250 meters D. 0 meter
Answer:
400 meters
Step-by-step explanation:
50 + 200 + 150 = 400
4. A Tesla dealership is having a sale on their cars. This week you can save 15% off
the total price. If the retail price of the Tesla is $30,190, what is the discount?
Answer:
25,661.5
Step-by-step explanation:
30160x15%=4528.50
30160-4528.50=25,661.50
PLSSSSSSSSSSSSSS HELPPP FOR REAL SOMEBODDYY REWARD BRAINLIEST!!!!!!!!!!!!!!!!!
Answer:
1. x = 3
2. (1, 0)
3. x = 3, -2
4. 144
5. -3 + 4√3
Step-by-step explanation:
Please help asap. This is khan acadamy
Answer:
xr 30 degrees
Step-by-step explanation:
the angles always add up to 180 sooo
53+97=150
180-150=30
there's how u solve these kinds of problems
hope this helps
Plz help I’ll give brainliest
1. y= -5
2. m=0
3. I dont know
1. 3x+4y=-20
x=0
3×0+4y=-20
0+4y=-20
y=-5
2. m=y/x
m=0/1
m= 0
3. Sorry
PLEASE ANSWER THIS ASAP
Answer:
Option D
is the correct....
A cylinder has a radius of 4 units and a height of 7 units. What is the volume in cubic units
Answer:
The answer is 352 cubic units
Bernard works for a business that sells and repairs tires. He can repair tires in an hour work day. What is Bernard's unit rate for the number of tires repaired in one hour?
Answer:
3 tires per hour
Step-by-step explanation:
Bernard works for a business that sells and repairs tires. He can repair 24 tires in an 8 hour work day. What is Bernard's unit rate for the number of tires repaired in one hour?
Number of tires repaired per day = 24 tires
Number of time used to repair tire per day = 8 hours
What is Bernard's unit rate for the number of tires repaired in one hour?
Number of tires repaired in one hour = Number of tires repaired per day / Number of time used to repair tire per day
= 24 tires / 8 hours
= 3 tires per hour
The unit rate for the number of tires repaired in one hour is 3 tires per hour
Mark leaves his house at 12:53
He gets to the shop at 14:23
His average speed was 20km/h
How far away is the shop from Mark's house?
Answer: His house is 43.33334 kilometers
Mr. Smith's class took a test! The scores of one group are listed below.
70, 60, 80, 85, 90
What is the mean absolute deviation of the data set?
Answer:
B
Step-by-step explanation:
Answer:
77
Step-by-step explanation:
add them all together and then divide by 5
help please 100 point
Answer:
Solution given:
we have
<A+<B=exterior <C[sum of two opposite interior angle of a triangle is equal to the exterior angle in a triangle]
So
3x-13+ 2x+4=116°
5x-9=116°
5x=116°+9°
x=125/5
x=25
Now
<A=3×25-13=62°
<B=2×25+4=54°
Answer:
[tex]3x - 13 + 2x + 4 = 166 \\ 5x - 9 = 116 \\ 5x = 166 + 9 \\ 5x = 125 \\ x = \frac{125}{5} \\ x = 25 \\ \\ a = 3 \times 25 - 13 = 62 \\ b = 2 \times 25 + 4 = 54[/tex]
Ethel had 4 feet of ribbion she used 1 1/2 feet for a craft project how many feet of ribbon does she have left
In the figure below, 7 ||
m. Find x.
Answer:
x+65°=120°[by alternate interior angle]
x=120°-65°
x=55°
Luke now takes 20 cards numbered 1 to 20. Show how the cards can
be paired to give an LCM of 60.
Answer:
Step-by-step explanation:
The pair members cannot be multiplied. Look at the last numbers that are prime starting with eleven
What are you going to pair these primes with
11 13 17 19
So they must be added (or maybe subtracted).
1 19
2 18
3 17
4 16
5 15
6 14
7 13
8 12
9 11
and 20 which no matter how you do this, there will be 1 card left over.
Each of them adds to 20 so the LCM is 20
helpppp please
On a map, 2 inches represent an actual distance of 28 miles. If the actual distance
between two cities is 322 miles, how many inches apart will the two cities be on the
map?
644 inches
23 inches
2 inches
28 inches
Please help me will mark brainliet
Answer:
The degree of the term is 5
Don't forget to mark me as brainliest
Please Please help me
Answer:
1. 30
Step-by-step explanation:
First, place the numbers from least to greatest.
11,13,23,37,45,58
Then, find the middle number (or two middle numbers).
In this case, the middle numbers are 23 and 37.
Third, we find the mean of these numbers.
23+37=60
60/2=30
So your answer is 30.
Repeat this method for the other problems.
Can someone please help me with this question
Answer
180 - x
Step-by-step explanation:
opposite angles of a quadrilateral inscribed in a circle are supplementary
Answer:
180-x !!!
Step-by-step explanation:
i had some time to think about it
What is the point-slope form of a line with slope
(-3, 6)?
nun
that contains the point
A. y- 3 = (x+3)
B. y+6 = {(x+3)
O C. y- 6 = - 3(x+ 3)
O D. y-6 = {(x+3)
Triangle ABC was reflected across an axis.
A. State what axis it was reflected across
B. Give the ordered pairs of the reflected triangle
Both antibiotics were prescribed in high dosage slow release capsules. The function C(x)=5log(x+1)+10 models the concentration of levofloxacin in mol/L over a time x, in hours. The function D(x) = 10log(x+1)+5 models the concentration of metronidazole in mol/L over a time x in hours. a) Which of the two drugs has a higher initial concentration in the blood stream? Justify your answer with an explanation. (2K, A) b) Determine when C(x) = D(x) algebraically and state what this represents in this situation. (6K, A, T) c) If Mathews is instructed to take both antibiotics at once the concentration levels could be modeled by the function(C+D)(x). How would the graph of (C+D)(x) differ from the individual graphs of C(x) and D(x)? Explain. (2T)
a) The initial concentration of levofloxacin (represented by C(x)) in the bloodstream is higher than the initial concentration of metronidazole (represented by D(x))
b) There is no algebraic solution for when C(x) = D(x) in this situation.
c) The graph of (C+D)(x) would show a steeper increase and higher values compared to the individual graphs of C(x) and D(x), indicating a higher concentration of the drugs when taken together.
a) The initial concentration of a drug in the bloodstream can be determined by evaluating the functions C(x) and D(x) at x = 0. Plugging in x = 0 into both functions, we find that C(0) = 5log(0 + 1) + 10 = 5log(1) + 10 = 5(0) + 10 = 10, and D(0) = 10log(0 + 1) + 5 = 10log(1) + 5 = 10(0) + 5 = 5. Therefore, the initial concentration of levofloxacin (represented by C(x)) in the bloodstream is higher than the initial concentration of metronidazole (represented by D(x)).
b) To find when C(x) = D(x), we set the two functions equal to each other and solve for x: 5log(x + 1) + 10 = 10log(x + 1) + 5. Subtracting 10log(x + 1) from both sides, we get 5log(x + 1) - 10log(x + 1) = 5. Simplifying, we have -5log(x + 1) = 5. Dividing by -5, we find log(x + 1) = -1. This equation can be rewritten in exponential form as 10^(-1) = x + 1, which simplifies to 0.1 = x + 1. Subtracting 1 from both sides, we get x = -0.9. However, since time cannot be negative, there is no solution to the equation. Therefore, there is no algebraic solution for when C(x) = D(x) in this situation.
c) The graph of (C+D)(x) would represent the combined concentration levels of both antibiotics when taken together. It would differ from the individual graphs of C(x) and D(x) by showing a higher overall concentration. Since (C+D)(x) is the sum of the two individual functions, the resulting graph would be the sum of their concentrations at each point in time. This means that at any given time, the concentration of the combined antibiotics would be the sum of the concentrations of levofloxacin and metronidazole at that time. The graph of (C+D)(x) would show a steeper increase and higher values compared to the individual graphs of C(x) and D(x), indicating a higher concentration of the drugs when taken together.
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If the family plans to move to their retirement home in 10 years, which pool would be more cost effective to install? How do
you know?
Answer:
Step-by-step explanation:
but is their any answer choices
PLEASE HELP!!
In a geometric sequence, a2=2, a3=12, and a4=72. Which equation can be used to find the nth term of the sequence, an?
an=2⋅10n−1
an=6⋅2n−1
an=13⋅6n−1
an=2n−1
Ik this is late, but people who are looking for the answer can see this.
Answer:
an =1/3*6^n-1
Step-by-step explanation:
You should plug in 2 for n in each equation, which, the correct one should give you 2. Then, to make sure, you plug in 3 in the equations that gave you 2.
Example:
an = 1/3 * 6 ^n-1
Plug in 2.
an = 1/3 * 6 ^2-1
an = 1/3 * 6 ^1
1/3 * 6 = 2
Step 2.
an = 1/3 * 6 ^3-1
an = 1/3 * 6 ^2
1/3 * 36 = 12
Hope this helps.
The correct equation which can be used to find the nth term of the sequence, an is,
⇒ a (n) = 1/3 × 6ⁿ⁻¹
What is an expression?Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.
Given that;
In a geometric sequence,
⇒ a₂ = 2, a₃ = 12 and a₄ = 72
Now, From option 3;
The equation is,
⇒ a (n) = 1/3 × 6ⁿ⁻¹
Put n = 2
⇒ a (2) = 1/3 × 6²⁻¹
⇒ a (2) = 1/3 × 6
⇒ a (2) = 2
Hence, This is the correct equation which can be used to find the nth term of the sequence, an.
Thus, The correct equation which can be used to find the nth term of the sequence, an is,
⇒ a (n) = 1/3 × 6ⁿ⁻¹
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The first day, Brian saw 31 birds and twice as many squirrels as birds. The second day, Brian saw 20 birds and 42 squirrels. Which of the following is a good estimation of how many birds and squirrels Brian saw in the two days?
Answer: A good estimation would be about 150.
Step-by-step explanation:
To estimate we can round instead of using exact numbers.
First day he saw about 30 birds and twice as many squirrels, meaning about 60 squirrels. This is about 90 total when added together.
Second day he saw 20 birds and about 40 squirrels so about 60 when added together.
Add day one and day two totals for...
90+60=150
Graph a line that has a slope of 5/2 and includes the point (-2, -7)