A paint manufacturer wants to determine the average drying time of a new interior wall paint. For n = 50 test areas of equal size he obtained a sample mean drying time of ¯x = 63.3 minutes and a sample standard deviation of s = 8.4 minutes. (a) (5 points) Construct the 95% confidence interval for the true mean µ. (b) (5 points) Suppose the population has a normal distribution, construct the exactly 95% confidence interval for the true mean µ. (c) (5 points) Suppose the population has a normal distribution, construct the 95% prediction interval for a new observation.
Answer:
a) the 95% confidence interval for the true mean µ is 60.971, 65.629
The exact 95% confidence interval for the true mean µ is 60.971, 65.629
P (x`- ∝ s/√n<u <x`+ ∝ s/√n) = 0.95
Step-by-step explanation:
n= 50
x`= 63.3
s= 8.4 minutes
∝= 95%= ±1.96
The formula for calculating the confidence interval is:
x`± ∝ s/√n
Putting the values
x`± 1.96 s/√n
63.3 ± 1.96(8.4/√50)
63.3± 2.3287
60.971, 65.629
a) the 95% confidence interval for the true mean µ is 60.971, 65.629
b) Putting the values
x`± 1.96 s/√n
63.3 ± 1.96(8.4/√50)
63.3± 2.3287
The exact 95% confidence interval for the true mean µ is 60.971, 65.629
c) The prediction level tells that the drying time of the wall from 60.971 to 65.629 minutes must be in the range 95 % of the time.
And is given by
P (x`- ∝ s/√n<u <x`+ ∝ s/√n) = 0.95
NEEDED ASAP PLZ!!!!!!!!!
The social studies teacher wants to know whether the students in the entire school prefer a model United Nations activity or a student government activity. The teacher draws a random sample from the following groups:
All teachers in the school
All boys in each grade
All students in each grade
All students in the social studies club
Which group best represents the population he should take a random sample from to get the best results for his survey? (5 points)
Group of answer choices
All teachers in the school
All boys in each grade
All students in each grade
All students in the social studies club
Answer:
All students in each grade
(Urgent) Worth 10 points 7.3
Answer:
m∡CBD = 135°
Step-by-step explanation:
m + 3m = 180
4m = 180
m = 180/4
m = 45
angle CBD is 3(45) = 135 degrees
find the length of AD. HELP MEEEE
Answer:
5.42
Step-by-step explanation:
hope this helped!! :)
What is equivalent to 0 = 2x2 - 16x – 18 when completing the
square?
Answer:
x = 1
x = -9
Step-by-step explanation:
(2x2 + 16x) - 18 = 0
2x2 + 16x - 18 = 2 • (x2 + 8x - 9)
x2 + 8x - 9
-9 + 1 = -8
-3 + 3 = 0
-1 + 9 = 8
2 • (x + 9) • (x - 1) = 0
2 = 0
x+9 = 0
x = -9
x-1 = 0
x = 1
x2 + 8x - 9 = 0
x2+8x = 9
(x+4) • (x+4) =
(x+4)2
x2+8x+16 = 25 and
x2+8x+16 = (x+4)2
(x+4)2 = 25
x = -4 + √ 25
x2 + 8x - 9 = 0
has two solutions:
x = -4 + √ 25
or
x = -4 - √ 25
- B ± √ B2-4AC
x = ————————
2A
A = 1
B = 8
C = -9
B2 - 4AC =
64 - (-36) =
100
-8 ± √ 100
x = —————
2
x = ( -8 ± 10) / 2
x =(-8+√100)/2=-4+5= 1.000
or:
x =(-8-√100)/2=-4-5= -9.000
Answer: x = 1
x = -9
Please no links, will report!
9514 1404 39318
Answer:
XY = 11.25
Step-by-step explanation:
Corresponding sides are proportional, so ...
XY/AB = XZ/AC
XY = (AB)(XZ/AC) = 5(18/8)
XY = 11.25
The amount that Jimmy paid for his meals the four days, $6.45, $21.38, $1.99, $7.99, $16, $0, $7.99, $18.95, $4.30, $10.35, $18.20. Calculate the median
Answer:
$7.99
Step-by-step explanation:
Arrange numbers in numerical order: $0, $1.99, $4.30, $6.45, $7.99, $7.99, $10.35, $16, $18.20, $18.95, $21.38.
Count how many numbers you have, 11.
11 is an odd number so, the number in the middle of the data set is the median.
Final answer: $7.99 is the median.
What is the definition of an irrational number?
A.
a negative number
B.
a number that can be expressed as a fraction, , where p and q are integers and q is not equal to zero
C.
a number that cannot be expressed as a fraction, , where p and q are integers and q is not equal to zero
D.
a number that can be written as a fraction but not as a decimal
Evaluate-n, when n=-4
Answer:
4
Step-by-step explanation:
-n =
-(-4) =
+4 =
4
Hope that helps!
-Sabrina
Which expression is equivalent to 4(5r+9)?
HELpPppPppPppPpppPppPppppppppppppppppppoopppppoppopppppppppp
Jdjxjjxx
Answer:
£140
Step-by-step explanation:
First count up the amount of full squares, then you see the partially filled squares and try find the match for it to fill the square. It ends up being 24 squares, meaning 24 square feet. That multiplied by £5, as that is the cost of red wood, gives you the answer of £140
Plz help if correct ill give Brainlyest
Answer:
taena mo
Step-by-step explanation:
taenamo bubung yawa
10 Mrs. Randall bought tickets to the art museum for all the fifth-grade students. Each ticket cost $12, and the total cost of the tickets was $1,152. How many fifth-grade students are there?
Answer:
Step-by-step explanation:
12s=1152 (divide each side by 12 to isolate s)
s=96
So there were 96 students.
quanto é dois mais dois divido por dois
Answer:
la respuesta es 2 (dois)
The baseball player threw the ball 30 feet to his teammate. How far would the throw be if measured in yards?
Answer:
10
Step-by-step explanation:
to convert to yard from feet you have to divide by 3
30/3-10 so he through the ball 10 yards
have a great day :D
Anthony needs some kitchen
appliances He found a mixer
for $90 and a microwave for
$42 What is the total bill
after adding 8% sales tax?
Work out m and c for the line:
y = x + 3
Step-by-step explanation:
Given equation
y = x + 3
Comparing with y = mx + c so
Slope (m) = 1
y-intercept (c) = 3
Hope it will help :)❤
Answer:
I don’t know if this is right, but I hope this helps!
Step-by-step explanation:
Find the area of the figure shown below and chose the appropriate result
Answer:
it's the first option or A
Step-by-step explanation:
well 9 * 10 is 90 which leaves you with the numbers 14 and 3 we used 10 so that gives us 4 and 3 multiply those and you get 12 so add 12 to 90 and you get 102 thus the answer is A
Find the value of x.
Pleaseeee I needddd helpppp!!!!!!
Answer:
x = 40
Step-by-step explanation:
Measure of an external angle of a circle = ½(difference of the intercepted arcs)
This means that:
½(PQ - RS) = m<T
m<T = x/2
PQ = (x + 70)°
RS = (x + 30)°
Plug in the values
½((x + 70) - (x + 30)) = x/2
½(x + 70 - x - 30) = x/2
½(x - x + 70 - 30) = x/2
½(0 + 40) = x/2
½(40) = x/2
20 = x/2
Multiply both sides by 2
20*2 = x
40 = x
x = 40
Round the fraction to 0, 1/2, or 1.
2/9
in a decimal[tex]\\4\frac{1}{5} \f}[/tex]
A coin is tossed 100 times. WHich portion would you use to find how many times you'd expect the coin to land on heads?
Answer:
i would use 1/2 because theres 2 sides on a coin and if you flip it 100 times then the probability of it landing on heads is about 50 out of 100
Step-by-step explanation:
WEEEEEEEEELLLLLLLLLLLL What is 1+1 :0 too confusion for my 1 braincell
Answer:
WELLLLLLLLLLLLLLLLLLLLLL it's 11 obviously. (or 2 ;P)
Step-by-step explanation:
i have 1/2 of a braincell :)
Answer:
1 + 1 is 2 BUT
2 + 2 is 5 ILLUMIATI CONFIRMED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Step-by-step explanation:
Guided Practice
Directions: Describe each pair of ratio. Write P if it is a proportion and NP if
not proportion.
1.) 4:6 = 20:24
2.) 9: 6 = 36:24
3.) 2:5 = 15:45
4.) 3:5 = 6:10
5.) 40: 16 = 5:2
Answer:
1) NP
2) P
3) NP
4) P
5) P
Step-by-step explanation:
re-write all the pairs into fractions
1.) [tex]\frac{4}{6} =\frac{20}{24}[/tex] {4 x 5 = 20} and {6 x 4 = 24} 5 ≠ 4
(basically both the underlined numbers need to be the same)I can do an explanation for each one if you need; just comment, cause I'll be on here for a while. Good luck! :D
Find the lateral surface area of the figure below. Round the the nearest tenths place.
help please !
A jar contains 8 red marbles, 10 blue marbles, and 2 yellow marbles. One marble is chosen at random. The color is recorded in the table and then it is returned to the jar. This is repeated 40 times. What is the experimental probability of choosing a yellow marble? Express your answer as a percent to the nearest whole number.
RED/14 BLUE/16 YELLOW/10
Answer:
1/4 or 25%Step-by-step explanation:
Experimental probability:
Pe = number of event occurred / number of attemptsProbability of yellow:
Pe(yellow) = 10/40 = 1/4 = 25%Which point is on the graph of y = 4x + 2? A (-2, -5 o B. (-4, -15) C. (4. 18) D. (0.1)
Answer:
The answer should be C
Step-by-step explanation:
I hope that helps you!
y=3/2x-9
I need to find the x-intercept and the y-intercept with work plsss
Hi there!
x-int: (6, 0)
y-int: (0, -9)
y = 3/2x - 9
Begin by finding the x-intercept. The x-intercept is located where y = 0, therefore:
0 = 3/2x - 9
Isolate for x by adding 9 to both sides:
9 = 3/2x
Divide both sides by 3/2x:
9 * 2/3 = x
x = 6. Thus, the x-intercept is at (6, 0).
Find the y-intercept by finding the y-value at which x = 0:
y = 3/2(0) - 9
y = -9. The y-intercept is at (0, -9).
Write the algebraic expression:
99 times the sum of y and 9
Can I please have help I will mark brainly est
Answer:
Hey mate......
Step-by-step explanation:
This is ur answer......
I believe its SQUARE! Cuz it says 4 right angles.....Hope it helps!
mark me brainliest pls.....
Follow me! :)