Answer:
Median: 9
Range: 4
mode: 9, 8, 11 (each appeared 2 times)
mean: 9.125 (average)
Step-by-step explanation:
There are 46 students in an elementary statistics class. On the basis of years of experience, the instructor knows that the time needed to grade a randomly chosen first examination paper is a random variable with an expected value of 5 min and a standard deviation of 4 min. (Round your answers to four decimal places.) A button hyperlink to the SALT program that reads: Use SALT. (a) If grading times are independent and the instructor begins grading at 6:50 P.M. and grades continuously, what is the (approximate) probability that he is through grading before the 11:00 P.M. TV news begins
Answer:
0.7704 = 77.04% probability that he is through grading before the 11:00 P.M. TV news begins
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 z-score 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 p-value, we get the probability that the value of the measure is greater than X.
Distribution of n values from a normal distribution:
If we take n values from a normally distributed variable, the mean is [tex]\mu*n[/tex], and the standard deviation is [tex]s = \sigma\sqrt{n}[/tex]
There are 46 students in an elementary statistics class. For each student, the mean is of 5 min and a standard deviation of 4 min.
This means that
[tex]\mu = 46*5 = 230[/tex]
[tex]s = 4\sqrt{46} = 27.13[/tex]
(a) If grading times are independent and the instructor begins grading at 6:50 P.M. and grades continuously, what is the (approximate) probability that he is through grading before the 11:00 P.M. TV news begins?
This is the probability that he finishes grading in 4 hours and 10 minutes, that is, 4*60 + 10 = 250 minutes, which is the pvalue of Z when X = 250.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
In this distribution
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{250 - 230}{27.13}[/tex]
[tex]Z = 0.74[/tex]
[tex]Z = 0.74[/tex] has a pvalue of 0.7704
0.7704 = 77.04% probability that he is through grading before the 11:00 P.M. TV news begins
Julisha poured 0.9 liter of water into an
empty flask. She boiled the water for 15
minutes then measured the amount of water
that remained. She found that 80% of the
water remained in the flask. Measured in
liters, how much water evaporated?
PLS I NEED HELP! ASAP.
Answer:
0.18
Rounded
0.2
Step-by-step explanation:
The base of the parallelogram is 8 units and its height is half of the base.
Find the area of the parallelogram.
A. 32 sq. units
B. 12 sq. units
C. 24 sq. units
D. 4 sq. units
Answer:
A. 32 sq. units
Step-by-step explanation:
To find the area of a parallelogram, multiply the base by the height.
In this case, the base is 8.
However, the height is unknown.
According to the word problem, the height is HALF the base.
To find half of the base, we divide it by 2.
8 / 2 = 4
4 is the height.
Lastly, multiply as usual.
Base ⋅ height:
8 x 4 = 32.
Therefore, the area of the parallelogram is 32 sq. units.
The surface area of a rectangular prism is 2,280 square feet. If the width and height are 20 and 15 feet, the length of the prism is 24 ft?
Answer:
The statement is trrue.
Step-by-step explanation:
Given that,
The surface area of a rectangular prism = 2,280 square feet
Width, b =20 feet
Height, h = 15 feet
The formula for the surface area of a rectangular prism is given by :
[tex]A=2(lb+bh+hl)[/tex]
Where
l is the length of the prism
Substitute all the values,
[tex]A=2(lb+bh+hl)\\\\2,280=2(20l+20\times 15+15l)\\\\1140=(20l+20\times 15+15l)\\\\1140=35l+300\\\\1140-300=35l\\\\35l=840\\\\l=24\ feet[/tex]
So, the length of the prism is equal to 24 feet.
Plz help me well mark brainliest if you are correct!!
Answer:
3
Step-by-step explanation:
1 hour = 60 minutes.
1/4 of an hour = 60 minutes / 4 = 15 minutes.
15 minutes / 5 minutes segments = 3
There are 3 five-minute segments in 1/4 of an hour
Answer:
C.
Step-by-step explanation:
Answer is C. because there are a total of 60 minutes in 1 hour. We know that there is 30 minutes in half a hour. Half of 30 minutes is 15 minutes and it takes 3 five minute segments to get 15 minutes.
You can do it like this 60 * 1/4 = 60/4
60/4 = 15/1
15 = 5 * 3
help I'll give brainliest!!!
LMNP is rotated 180° clockwise around the origin. M 3, 4) N54) 2 RE PX90) What are the coordinates of L'? A. L'(1,0) B. L'(-1,0) c. l'(0,1) D. L'(0, -1)
Answer:
It’s (-3, -4)
Step-by-step
I did this program too.
A triangle has a perimeter of 74 inches. If the three sides of the triangle are n, 3n+6, and 3n−2, what is the length of each side?
Answer:
N=10
3n+6=36
3n-2=28
Step-by-step explanation:see photo
Susan was carrying a pitcher that contained 2/3 of a gallon of lemonade to the table for lunch. She slipped and spilled 1/4 of the lemonade in the pitcher. What fraction of a gallon of lemonade did she spill?
Answer:
Susan spilled 1/6 of a gallon of lemonade.
Step-by-step explanation:
Since Susan was carrying a pitcher that contained 2/3 of a gallon of lemonade to the table for lunch, and she slipped and spilled 1/4 of the lemonade in the pitcher, to determine what fraction of a gallon of lemonade did she spill the following calculation must be performed:
2/3 = 0.6666
0.666666 x 1/4 = X
0.166666 = X
0.166666 = 1/6
Therefore, Susan spilled 1/6 of a gallon of lemonade.
whats 3/10 out of 140?
Answer:
you have got your mark in fraction.
Answer: the answer is 42.
Step-by-step explanation:
This is how you solve.
Take 140 and divide by 10.
You would get 14.
then, times 14 by 3 or add it 3 times.
14+14+14 is equal to 42.
hope This helped!
I need help with this if your right I will mark uou
Answer:
I think it's a
Step-by-step explanation:
A bag contains 56 marbles: 7 red, 8 green, 11 yellow, 17 brown, and 13 blue.
If a marble is chosen at random, what is the probability that the marble is green?
A.1/5
B.1/6
C.1/7
D.1/8
Answer: D 1/8
Step-by-step explanation: hope this help
Answer:
1/5
Step-by-step explanation:
You count how many colors there are and make how many color as your denominator [5 colors(Red, Green, Blue, Yellow, and Brown)] and find out what color was picked as your numerator [Green(1 color)].
70×2+20×30+19
are you okk guys❤
Answer: ...BEDMAS..
steps,..
70×2+20×30+19
140+600+19
740+19
=759
.... and I'm not all fine lol...wau guy??
a machine shop has a fixed cost of $2000 to produce new bolts. The cost of materials and labor to produce each individual bolt is $8.50. Which of the following functions models the average cost per bolt for the company to produce x bolts, where
x>1?
Answer:
(8.50x + 2000)/x and x>1
Step-by-step explanation:
Well, this may not be the exact answer, as it seems you have the choices unlisted--if they even exist at all. But, I'll make do with what I've provided, so
In the question, it says the collective cost for each individual bolt is $8.50, and that we can use the variable x to represent the number of bolts the company wishes to produce. So, this can be shown using 8.50x.
The fixed cost is set in stone, so no alterations need to be applied, and only cause the total to amount to a greater number. So, we end up with (8.50x + 2000)/x and x>1 is the rule for the values of x. Essentially, all that means is that the company will always produce more than one bolt.
An inequality is two expressions that are
NOT equal, unlike an equation.
True
False
2×(c power of 2-5)for c =4
Select the correct answer
Answer:
number 3
Step-by-step explanation:
thats my calcue
Select all the equations where r 3 is a solution.
Answer:
The right answers are 1,4 and 6
Answer:
x-3 =0
6=2x
x^2 = 9
Step-by-step explanation:
substitute the values, and you will get the answer!
have a great day!!
The experimental probability that Kevin will catch a
fly ball is equal to 3/4. About what percent of the
time will Kevin catch a fly ball?
A. 77%
B.55%
C.88%
D.75%
Answer:
C.
Step-by-step explanation:
Answer:
75%
Step-by-step explanation:
The fraction 3/4 is equivalent to 75%. Therefore, the percent Kevin will catch a fly ball is 75%.
Write down and simplify expression of the perimeter of the shape below.
Simplified Please !
Answer:
[tex]P = 4x+4[/tex]
Step-by-step explanation:
Given
The attached triangle
Required
Determine the perimeter (P)
This is calculated by adding the measure of the three sides.
So, we have:
[tex]P = 2x-3 + x + 5 +x + 2[/tex]
Collect like terms
[tex]P = 2x +x +x-3 + 5 + 2[/tex]
[tex]P = 4x+4[/tex]
Factorize
[tex]P = 4(x+1)[/tex]
Hence, the perimeter is 4x + 4 or 4(x + 1)
Question
The area of a rectangle is 1,367 square feet. The length is 60 feet. What is the width?
Step-by-step explanation:
[tex] \frac{1367}{60 } = 22.783[/tex]
Which of the expressions shown has a GCF of 5ab^2 with 15ab^3?
A. 30ab^2
B.30a^2b^5
C. 25ab^2
D. 5ab^2
Answer:
The greatest common factor of 5ab^2 and 15ab^3 is 5ab^2
The greatest common factor between the two expressions will be 5ab²
What is the greatest common factor?
The greatest common factor is the largest positive number which can be divided into given numbers evenly.
Here the two numbers are:-
5ab² and 15ab³ or 5ab² and 5ab² x b
So we can see that the highest common factor between the two numbers will be 5ab².
To know more about the greatest common factor follow
https://brainly.com/question/219464
#SPJ2
he volume of a cylinder varies jointly with the base (area) and the height. The volume is 40inches^3 when the base (area) is 6inches^2 and the height is 20inches. Find the volume of the cylinder (after finding the variation constant) when the base (area) is 8inches^2 and the height is 12inches.
Answer:
Variation factor k = 1/3
New volume when the base (area) is 8inches^2 and the height is 12inches is 32 in3
Step-by-step explanation:
As we know,
The volume of cylinder (V) is given by πr²h
Here πr² = base area and h is the height of the cylinder
V ∞ πr²h
V = kπr²h
Substituting the given values, we get
40 = 6 x 20 x k
40 = 120k and
k = ⁴⁰/₁₂₀
= ¹/₃.
Volume when base area = 8in² and h = 12 inch
V = 8 x 12 x ¹/₃
V = 32in³
I need help on number one
answer is 9
Change the sign of the exponent by rewriting the base as its reciprocal
3^2
raise 3 to the power of 2
you get 9
Please help me but no links
Answer:
I think you got to time it all togther and the answer would be 531.44m^3
Step-by-step explanation:
(5.2×7×14.6)mmm
(36.4×14.6)mmm
531.44m^3
ASAP!! simplify x^-2 show work
Answer:
1/x^2
Step-by-step explanation:
exponent rule: a^-b = 1/a^b
x^-2 = 1/x^2
Answer:
[tex] \frac{1}{ {x}^{2} } [/tex]
Step-by-step explanation:
1) Remove parentheses.
[tex] {x}^{ - 2} [/tex]
2) Use negative power rule: x^-a = 1/x^a.
[tex] \frac{1}{ {x}^{ 2} } [/tex]
hence, the answer is 1/x^2.
The posted speed limit is 45 miles per hour.
Choose all the metric measures that are faster than 45 miles
per hour.
A. 45 km per hour
B. 64.1 km per hour
C. 86.4 km per hour
D. 91 km per hour
E. 112.3 km per hour
SAT scores: The College Board reports that in 2009, the mean score on the math SAT was 582 and the population standard deviation was =σ120. A random sample of 20 students who took the test in 2010 had a mean score of 515. Following is a dotplot of the 20 scores. (a) Are the assumptions for a hypothesis test satisfied? Explain. (b) If appropriate, perform a hypothesis test to investigate whether the mean score in 2010 differs from the mean score in 2009. Assume the population standard deviation is =σ120. What can you conclude? Use the =α0.10 level of significance and the critical value method.
Answer:
we can conclude that there is no significant evidence to conclude that the mean score in 2010 differs from the mean score in 2009.
Step-by-step explanation:
H0 : μ = 582
H1 : μ < 582
Test statistic :
T = (xbar - μ) ÷ σ/√n
Xbar = 515 ; n = 20 ; σ = 120
T = (515 - 582) ÷ 120/√20
T = -67 / 26.832815
T = 2.50
Pvalue at t score = 2.50 ; df = 19 is 0.0187
At α = 0.0187
Pvalue > α ; Hence, we fail to reject the Null
Hence, we can conclude that there is no significant evidence to conclude that the mean score in 2010 differs from the mean score in 2009.
Factorise the following completely: (4 marks)
a)a) 81
Answer:
Learn the factors of 92, and the factors of 93, and the factors of 94.All three of these numbers are composite numbers
If you are trying to build credit by using a credit card, each time you make a purchase with the credit card, deduct that amount from your checking account. That way, when your credit card bill is due, you will have enough to pay the credit card off in full. Kathy Lehner is going to start doing this. She plans on paying her credit card bill in full this month. How much does she owe with a 6% APR and the following transactions? (Round your answer to the nearest cent.)
31-day billing cycle
10/1 Previous balance $ 1,164
10/3 Credit $ 79 cr.
10/12 Charge: King Soopers $ 148
10/15 Payment $ 310 cr.
10/25 Charge: Delta $ 321
10/30 Charge: Holiday Fun $ 61
What would be the amount owed?
Answer:
12593
Step-by-step explanation:
tell me if this hepls
Ur should be noted that Kathy Lehner owes approximately $1,311.97.
How to calculate the amountPrevious balance (10/1): $1,164
Credit (10/3): $79 credit. This reduces the balance, so the new balance is $1,164 - $79 = $1,085.
Charge: King Soopers (10/12): $148 charge. This increases the balance, so the new balance is $1,085 + $148 = $1,233.
Payment (10/15): $310 credit. This reduces the balance, so the new balance is $1,233 - $310 = $923.
Charge: Delta (10/25): $321 charge. This increases the balance, so the new balance is $923 + $321 = $1,244.
Charge: Holiday Fun (10/30): $61 charge. This increases the balance, so the new balance is $1,244 + $61 = $1,305.
Interest calculation: $1,305 * (6% * (31/365)) = $6.9698 (rounded to the nearest cent, which is $6.97).
Finally, to determine the total amount owed, we add the balance and the interest:
Total amount owed: $1,305 + $6.97 = $1,311.97
Therefore, Kathy Lehner owes approximately $1,311.97.
Learn more about amount
https://brainly.com/question/25720319
#SPJ2
Can you help me solve this it’s pretty easy but for you guys
Answer:
x - 81 = 321
adding 81 on both sides
x-81+81= 321+81
x= 402
Answer:
402
Step-by-step explanation:
81+321=402-321=81 n=402