Answer:
x = 4
Step-by-step explanation:
x + x + 6 + 6 = x + 8 + 8
2x + 12 = x + 16
2x + 12 - 12 = x + 16 - 12
2x + 0 = x + 4
2x = x + 4
2x - x = x + 4 - x
2x - x = x - x + 4
x = 0x + 4
x = 0 + 4
x = 4
Chequando Respuesta :
x = 4
x + x + 6 + 6 = x + 8 + 8
(4) + (4) + 6 + 6 = (4) + 8 + 8
4 + 4 + 6 + 6 = 4 + 8 + 8
8 + 6 + 6 = 12 + 8
14 + 6 = 20
20 = 20
Ambos lados de la ecuacio'n son igual cuando x = 4, y esto confirma que la respuesta es corecta, que x = 4 en este problema.
a normal distribution has a mean of 56 and a standard deviation of 8. Find the percentage of data values that are in the given interval. Use the curve to aid you.
Answer:
12) Between 40 and 64 = 0.815
13) Between 32 and 40 = 0.0235
14) Between 56 and 64 = 0.34
15) At most 56 = 0.515
16) At least 72 = 0.025
17) At most 64 = 0.855
Explanation:
To answer this, we will convert each of the values into their standardized form to make this easier.
The standardized score for any value is the value minus the mean then divided by the standard deviation.
z = (x - μ)/σ
x = Each value
μ = Mean = 56
σ = Standard deviation = 8
12) Between 40 and 64
For 40,
z = (x - μ)/σ = (40 - 56)/8 = (-16/8) = -2
For 64
z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1
So,
Between 40 and 64 = Between -2 and 1
From the curve, noting that the central point is the mean, with standard score of 0, the lines before it move in step of 1 standard deviation towards the negative side, that is, -1, -2, etc. And the lines before the central point move towards the positive side, that is, 1, 2, 3, etc.
So,
Between -2 and 1 = 0.135 + 0.34 + 0.34 = 0.815
13) Between 32 and 40
For 32,
z = (x - μ)/σ = (32 - 56)/8 = (-24/8) = -3
For 40,
z = (x - μ)/σ = (40 - 56)/8 = (-16/8) = -2
So,
Between 32 and 40 = Between -3 and -2 = 0.0235
14) Between 56 and 64
For 56,
z = (x - μ)/σ = (56 - 56)/8 = (0/8) = 0
For 64,
z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1
Between 56 and 64 = Between 0 and 1 = 0.34
15) At most 56
For 56,
z = (x - μ)/σ = (56 - 56)/8 = (0/8) = 0
At most 56 = At most 0 = 0.0015 + 0.0235 + 0.15 + 0.34 = 0.515
All the regions before z = 0)
16) At least 72
For 72,
z = (x - μ)/σ = (72 - 56)/8 = (16/8) = 2
At least 72 = At least 2 = 0.0235 + 0.0015 = 0.025
(All the regions from z = 2 to the end)
17) At most 64
For 64,
z = (x - μ)/σ = (64 - 56)/8 = (8/8) = 1
At most 64 = At most 1 = 0.0015 + 0.0235 + 0.15 + 0.34 + 0.34 = 0.855
(All the regions before z = 1)
Hope this Helps!!!
Lucy and Ayu sold a total of 1,080 iPads. Lucy sold 7 times as many as Ayu. How many did each sell
Answer:
let L=lucy and A=ayu
l+a=1080
l=7a 7a+a=1080
8a=1080 8a/8=1080/8
ayu=135
l=7a l=7×135
l=945 so:-135+945=1080
Lucy sold 945 iPads and Ayu sold 135 iPads
What is an equation?"It is a mathematical statement which consists of equal symbol between two algebraic expressions."
For given question,
Let Lucy and Ayu sold 'x' and 'y' iPads respectively.
Lucy and Ayu sold a total of 1,080 iPads.
So, we get an equation,
⇒ x + y = 1080 ...............(i)
Lucy sold 7 times as many as Ayu.
So we get the second equation as,
⇒ x = 7y ................(ii)
Substitute above value of x in equation (i)
⇒ x + y = 1080
⇒ 7y + y = 1080
⇒ 8y = 1080
⇒ y = 135
This means, Ayu sold 135 iPads
Substitute above value of y in equation (ii)
⇒ x = 7(135)
⇒ x = 7 × 135
⇒ x = 945
This means, Lucy sold 945 iPads.
Therefore, Lucy sold 945 iPads and Ayu sold 135 iPads
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On Saturday, Ahmed walks his dog 0.5 mile. On the same day, Latisha walks her dog 0.7 times as far as
Ahmed walks his dog.
How far does Latisha walk her dog on Saturday?
Latisha walks her dog mile(s) on Saturday. I have it due by tomorrow at 7 am please help, don’t put the links!!
Q1. If sinθ = 3/5 and cosθ = 4/5, Find the value of tanθ (Use Pythagorean Identity)
Q2. If sinθ = 3/5 and cosθ = 4/5, Find the value of tanθ (Use Trignometric Identity)
Step-by-step explanation:
[tex]sinθ = \frac{3}{5} \: \: cosθ = \frac{4}{5} \\ now \\ tanθ = \frac{sinθ}{cos θ } \\ = \frac{3}{5 } \div \frac{4}{5} \\ = \frac{3}{5} \times \frac{5}{4} \\ = \frac{3}{4} [/tex]
Hope it will help :)❤
A taxi charges 2.50 plus .50 fee for each mile. If the ride costs 7.50 how many miles did he travel
Answer: 10 miles
Step-by-step explanation:
Mile 1: 3.00
Mile 2: 3.50
Mile 3: 4.00
Mile 4: 4.50
Mile 5: 5.00
Mile 6: 5.50
Mile 7: 6.00
Mile 8: 6.50
Mile 9: 7.00
Mile 10: 7.50
Find the average rate of change of the function between the given values of x.
y = -5x - x2 between 2 and x = 6.
Answer:
The average rate of change is of -13.
Step-by-step explanation:
Average rate of change:
The average rate of change of a function in an interval [a,b] is given by:
[tex]A = \frac{f(b) - f(a)}{b - a}[/tex]
In this question:
Between 2 and 6. So
[tex]f(6) = -5(6) - 6^2 = -30 - 36 = -66[/tex]
[tex]f(2) = -5(2) - 2^2 = -10 - 4 = -14[/tex]
[tex]A = \frac{-66 - (-14)}{6 - 2} = \frac{-66 + 14}{4} = \frac{-52}{4} = -13[/tex]
The average rate of change is of -13.
a new optical illusion is posred on the internet. Write a recursive formula to describe the pattern. The, write the explicit formula that can be used to find the number of times the optical illusionis shared after eight hours.
Answer:
hope this helps
The solution is 3,27,680
The geometric progression is given by aₙ = a ( r )ⁿ⁻¹ , where r = 4 is the common ratio and after 8 hours a₈ = 3,27,680
What is Geometric Progression?A geometric progression is a sequence in which each term is derived by multiplying or dividing the preceding term by a fixed number called the common ratio.
The nth term of a GP is aₙ = arⁿ⁻¹
The general form of a GP is a, ar, ar2, ar3 and so on
Sum of first n terms of a GP is Sₙ = a(rⁿ-1) / ( r - 1 )
Given data ,
Let the first term of the geometric sequence be a₁ = 20
Let the second term a₂ = 80
So , the common ratio r = second term / first term
On simplifying the equation , we get
Common ratio r = 80/20
Common ratio r = 4
Now , the explicit formula for the GP is
aₙ = a ( r )ⁿ⁻¹ , where n is the number of hours
aₙ = 20 ( 4 )ⁿ⁻¹
So , after 8 hours ,
Substitute the value of n = 8 in the equation , we get
a₈ = 20 ( 4 )ⁿ⁻¹
a₈ = 20 ( 4 )⁷
a₈ = 3,27,680
Therefore , the value of a₈ = 3,27,680
Hence , the equation is aₙ = 20 ( 4 )ⁿ⁻¹
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f(x)=x² g(x) = (x + 3)2 +5 We can think of g as a translated (shifted) version of f. Complete the description of the transformation. Use nonnegative numbers. To get the function g, shift f up/down by units and to by units. the right/left
Answer:
Me puedes informar mas?
Noise levels at 5 airports were measured in decibels yielding the following data:
117,118,140,116,119
1. Construct the 90% confidence interval for the mean noise level at such locations. Assume the population is approximately normal.
2. Calculate the sample mean for the given sample data.
3. Find the critical value that should be used in constructing the confidence interval.
Answer:
1. 112.364<μ,131.636
2. mean = 122
3. critical value = +-2.1318
Step-by-step explanation:
117+118+140+116+119/5
= 610/5
= 122
the sample mean = 122
the sample standard deviation
s² = (117-122)²+(118-122)²+(140-122)²+(116-122²)+(119-122)²/5-1
= 25+16+324+36+9/4
= 410/4
= 102.5
s² = 102.5
s = √102.5
s= 10.12
SE = s/√n
= 10.12/√5
= 4.52
degree of freedom = 5-1 = 4
critical value of t = +-2.1318 using soft ware
confidence interval =
mean +- t(SE)
122-(2.1318)(4.52), 122+(2.1318)(4.52)
= [112.364, 131.636]
112.364<μ,131.636
therefore these are the answers in the ordre it was given in the question
1. 112.364<μ,131.636
2. mean = 122
3. critical value = +-2.1318
Police response time to an emergency call is the difference between the time the call is first received by the dispatcher and the time a patrol car radios that it has arrived at the scene. Over a long period of time, it has been determined that the police response time has a normal distribution with a mean of 7.2 minutes and a standard deviation of 2.1 minutes. For a randomly received emergency call, find the probability that the response time is between 3 and 9 minutes. (Round your answer to four decimal places.)
Answer:
0.7823 = 78.23% probability that the response time is between 3 and 9 minutes.
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.
Normal distribution with a mean of 7.2 minutes and a standard deviation of 2.1 minutes.
This means that [tex]\mu = 7.2, \sigma = 2.1[/tex]
Probability that the response time is between 3 and 9 minutes.
This is the pvalue of Z when X = 9 subtracted by the pvalue of Z when X = 3. So
X = 9
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{9 - 7.2}{2.1}[/tex]
[tex]Z = 0.86[/tex]
[tex]Z = 0.86[/tex] has a pvalue of 0.8051
X = 3
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{3 - 7.2}{2.1}[/tex]
[tex]Z = -2[/tex]
[tex]Z = -2[/tex] has a pvalue of 0.0228
0.8051 - 0.0228 = 0.7823
0.7823 = 78.23% probability that the response time is between 3 and 9 minutes.
Aubree is going to invest $27,000 and leave it in an account for 10 years. Assuming the interest is compounded continuously, what interest rate, to the nearest tenth of a percent, would be required in order for Aubree to end up with $39,000?
Answer:
3.7%
Step-by-step explanation:
simple
ANSWER ASAP FOR BRAINIEST AND 100 POINT ASAP
Find the value of x in the triangle.
The total measure of all the angles in a triangle is 180°.
Since there is already a 90° angle, the other 2 angles must also add up to 90°.
The only answer that fits is x = 9.
Check:
9x7 = 63°
3x9 = 27°
Add up = 90°
:)
C (x=18)
is your answer
Lei is icing some cupcakes. She has 3/4 cups of frosting. Each cupcake needs 3/16 cup of frosting. How many can she frost?
Answer:
4
Step-by-step explanation:
3/4÷3/16
3/4×16/3
3•16=48
4×3=12
48÷12=4
Quadrilateral GHIJ is dilated by a scale factor of 22 to form quadrilateral G'H'I'J'. What is the measure of side H'I'?
Answer:
[tex]H'I = 48[/tex]
Step-by-step explanation:
Given
See attachment for complete question.
From the attachment, we have:
[tex]GH=16.5[/tex]
[tex]HI =24[/tex]
[tex]IJ = 17[/tex]
[tex]JG =32.2[/tex]
[tex]k = 2[/tex] --- Scale factor
Required
Find H'I
The corresponding side of H'I is HI.
So:
H'I is calculated as:
[tex]H'I = k * HI[/tex]
This gives:
[tex]H'I = 2 * 24[/tex]
[tex]H'I = 48[/tex]
Answer I to j is 42
Step-by-step explanation:
In a recent academic year, many public universities in the United States raised tuition and fees due to a decrease in state subsidies. The change in the cost of tuition, a shared dormitory room, and the most popular meal plan from the previous academic year for a sample of 10 public universities were as follows:
$1,589, $593, $1,223, $869, $423, $1,720, $708, $1,425, $922 and $308.
a. What is the mean and median change in the cost? (Explain how you obtain your answer.)
b. What is the five-number summary of the change in the cost? (Explain how you obtain your answer.)
c. What is the standard deviation of the change in the cost? (Explain how you obtain your answer.)
d. The middle 50% of the change in the cost is spread over what value? (Explain how you obtain your answer.)
e. What is the coefficient of variation of the change in cost? (Explain how you obtain your answer.)
f. What are the (absolute values of) the Z scores of the change in cost?
Answer:
1. mean = 980 median = $895.5
2. 308, 593, 895.5, 1425, 1720
3. 491.7978
4. 895.5
5. 50.28%
Step-by-step explanation:
1. mean $1,589+$593+$1,223+$869+$423+$1,720+$708+$1,425+$922+$308/10
= 9780/10
= $978
median
We first arrange the values in ascending order
308,423,593,708,869,922,1223,1425,1589,1720
number of observation is even so we pick the 2 values in the middle and divide by 2
= 869+922/2
= $1791/2
$895.5
2. five number summary of change
the botom half of th dta set = 308,423,593,708,869
minimum value = 308
n = 5
median = 593 = q1
from 1, q2 = median = $895.5
the upper half of data
922,1223,1425,1589,1720
n = 5
median = $1425
maximum value = $1720
the five number summary of change in cost is therefore
308, 593, 895.5, 1425, 1720
3. standard deviation
[tex]s =[\sqrt{x-barx} ]^{2} \frac{1}{n-1}[/tex]
bar x is the mean = 978
($1,589-978)²+ ($593-978)²+ ($1,223-978)²+ ($869-978)+ ($423-978)²+ $1,720-978)²+($708-978)²+ ($1,425-978)²+ ($922-978)²+ ($308-978)²
= 2176786
=[tex]\sqrt\frac{1}{10-1} {2176786} \\\sqrt{ \frac{2176786}{9}[/tex]
= [tex]\sqrt{241865.1}[/tex]
= 491.7978
4. middle 50% is spread over the median, which is 895.5
5. coefficient of variation
= s/bar x * 100
= 491.7978/978 * 100
= 49179.78/978
= 50.28%
6. z score = x - mean/s
x = 1589
= 1589-978/491.7978
= 1.2424
for x = 593
593-978/491.7978
= -0.7828
= 0.7828
for x = 1223
1223-978/491.7978
= 0.4982
for x = 869
869-978/491.7978
= -0.2216
= 0.2216
for x = 423
423-978/491.7978
= -1.1285
= 1.1285
x = 1720
1720-978/491.7978
z = 1.5088
for x = 708
708-978/491.7978
= -0.5490
= 0.5490
for x = 1425
1425-978/491.7978
= 0.9089
for x = 922
922-978/491.7978
= -0.1139
= 0.1139
for x = 308
308-978/491.7978
= -1.3624
= 1.3624
What is the value of the expression below when x=7?
6x+ 10
A. 52
B. 67
C. 42
D.77
Answer:
52
Step-by-step explanation:
when a letter is next to a number like that and they tell u what the letter is u times it so 6x7+10=52 hope this helped :P
HELP PLEASE BRAINLYIST
Examine the diagram. It is not drawn to scale.
Wh at is the m angle 3?
Х
m angle 3=
Answer:
isn't it just 50°
Step-by-step explanation:
180=a straight line.
you are given 75° and 55°
75+55=130
180-130
Answer:
105
Step-by-step explanation:
Chupapi
Some loser deleted my answers
That's why it says 1 answer and 1.5k people helped
2. Which are not the measures of the sides of a right triangle?
A. O 1, 3,3
B.O 2,2,3,4
cks 1, 3,2
D.O
Answer:
B. because there are too many side lengths to be a triangle
A farmer knows that a grocery store will reject a shipment of his vegetables if more than 4% of the vegetables contain blemishes. He inspects a large truckload of tomatoes to determine if the proportion with blemishes (p) exceeds 0.04. He selects an SRS of 150 tomatoes from the more than 2,000 tomatoes in the truck. Suppose that 8 tomatoes sampled are found to have blemishes. Which of the assumptions for inference about a proportion is violated, if any?
a. Large Counts: np > 10
b. Large Counts: n(1 – p) > 10
c. The sample is a random sample of the entire population.
d. 10% condition: the sample size is less than 10% of the population.
e. There do not appear to be any violations.
Answer:
Assumption A is violated
Step-by-step explanation:
x = number of blemishes = 8
n = sample size = 150
proportion = x/n = 8/150 = 0.0533
1. large counts: np> 10
= 150 * 0.0533 >10
= 7.995 > 10
this assumpton is obviously violated. 7.995 is not greater than 10
2. Large Counts: n(1 - p) > 10
150(1-0.0533)>10
150-7.995 > 10
142.005> 10
there is no violation. The assumption is satisfied
3. This assumption is satisfied. this is because the tomatoes were selected using simple random sampling.
4. 10% of the population = 0.1 * 2000 = 200
the sample size = 150
150 < 200
this assumption is satisfied
The diameter of a circle is 3 meters. What is the circumference?
Answer:
C≈9.42m
Using any of this formulas
C=2πr
C=2πrd=2r
Solution:
C=πd=π·3≈9.42478m
Find the slope of the line
O 1/3
O 6/2
0 -3/1
03/1
Answer:
6/2
Step-by-step explanation:
The slope of the given line is 3/1, Option D is correct.
The given line is passing through the points (1, 3) and (-1, -3)
The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is
m=y₂-y₁/x₂-x₁
Plug in the values of points (1, 3) and (-1, -3) in the formula.
m= -3-3/-1-1
=-6/-2
Divide numerator and denominator by 2
We get 3
Slope of the line is 3.
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in a book reading contest students read as many books as they can in one week. the number of books read by each student are given, use the data to make a histogram
2, 10, 5, 4, 1, 3, 2, 6, 4, 8, 1, 3, 5
Answer:
C
Step-by-step explanation:
Process of elimination. A) had the wrong numbers on the bottom. B) has the right information but it's too narrow. D) has the wrong information. I just took the quiz and got this questions right. Hope this helps!
Answer:
C is the approximant answer
Jerel runs 5 days each week. On each of 4 days, he runs 2.3 km. If Jerel runs a total of 14 km, how many kilometers does he run on the fifth day? a3.8km b4.8km c5.8km d4.7km
Answer:19
Step-by-step explanation:
What ordered pairs are the solutions of the system of equations shown in the graph below?
Answer:
(-3,1) and (-8,6)
Step-by-step explanation:
Hey gabymcarrillo!
The solution is always the place where the two lines intersect.
Our first answer: go 3 left on the x- axis, and then go 1 up on the y- axis. This results in (-3,1)
Our second answer: go 8 left on the x- axis, then go 6 up on the y- axis. This results in (-8,6)
Hope a helped, have a nice day!
-Aadi x
Calculate the volume of the given pyramid to the nearest tenth
Answer:(A.)
Step-by-step explanation:The reason why its a its because that 13x8=104x17=1,768/3=589.3. Therefore 589.3 can not be round to the nearest tenth.
It costs $6 per hour for a park to water the grass. How much will it cost to water the grass for
7/3
hours?
Answer:
I think the answer is $14 hope this helps!
Step-by-step explanation:
-(3x + 1) > -7+3x
Plz help with this
Answer:
x<1
Step-by-step explanation:
Treat it like a normal equation
Distribute: -3x-1>-7+3x
Isolate x: -6x>-7+1
Because we are dividing by a negative number, we need to flip the sign
x<1
Answer:
0, -1
Step-by-step explanation:
1. Plug in for 5:
-(15 + 1) > -7 + 15
-16 > 8 (FALSE)
2. Plug in for 1
-(3 + 1) > -7 + 3
-4 > -4 (FALSE, they are equal)
3. Plug in for 0
-(0 + 1) > -7 + 3(0)
-1 > -7 (TRUE)
4. Plug in for -1
-(-3 + 1) > -7 - 3
-(-2) > -10
2 > -10 (TRUE)
5. Plug in for 20
-(60 + 1) > -7 + 60
-66 > 53 (FALSE)
6. Plug in for -32
-(96 + 1) > -7 + 96
-97 > 89 (FALSE)
You can find the answer by just plugging in for x. It's very easy and the rest is just addition and multiplication, so please put some effort. Hope this helps! :)
00:00
The city council in Middlefield wants to know if residents are in favor of a traffic camera at the main intersection in town. Drag tiles to match each
term to the example it best describes. Each tile may be used only once.
Representative Sample
Population
NOT a Representative Sample
Term
Example
Drivers who reside in Middlefield
Residents of Middlefield
Residents randomly chosen from the town register
Answer:
Matching Tiles with Terms:
Term Example
NOT a Representative Sample Drivers who reside in Middlefield
Population Residents of Middlefield
Representative Sample Residents randomly chosen from the
town register
Step-by-step explanation:
Population includes all the residents of Middlefield.
Representative Sample is a population subset that accurately reflects the characteristics of the population. For example, the subset of residents who are randomly chosen from the town register is an unbiased and representative sample.
NOT a Representative Sample: For example, drivers who reside in Middlefield do not represent the characteristics of the population of Middlefield.
Combine the like terms to create an equivalent expression,
Зу +6 – у
HELPPPPPP NOWWWW
100 points
Answer: 2y+6
Step-by-step explanation:
Answer:
x and y
Step-by-step explanation:
The length of stay at a specific emergency department in Phoenix, Arizona, in 2009 had a mean of 4.6 hours with a standard deviation of 2.9. Assume that the length of stay is normally distributed.
a. What is the probability of a length of stay greater than 10 hours?
b. What length of stay is exceeded by 25% of the visits?
c. From the normally distributed model, what is the probability of a length of stay less than 0 hours? Comment on the normally distributed assumption in this example.
Answer:
a) the probability of a length of stay greater than 10 hours is 0.03144
b) the length of stay is exceeded by 25% of the visits is 6.5 hrs
c)
P( X < 0 ) = 0.0559
The probability of length of stay less than 0 hours is 0.0559, length of stay cannot be less than 0. When the normal model is used, we assume that the LOF is approximately normally distributed.
The LOF is better modeled by the normal distribution near the mean and worse in the tails.
The probabilities in the left tail for the vales of X < 0 can be neglected.
Step-by-step explanation:
Given that;
mean μ = 4.6
standard deviation σ = 2.9
let x represent length of stay;
a. What is the probability of a length of stay greater than 10 hours?
p( x > 10 ) = p( x-μ/σ > 10-4.6 / 2.9 )
= p( Z > 1.86)
= P( Z < - 1.86 )
FROM THE Z SCORE TABLE;( Z < - 1.86 ) = 0.03144
p( x > 10 ) = 0.03144
Therefore, the probability of a length of stay greater than 10 hours is 0.03144
b) What length of stay is exceeded by 25% of the visits?
p( X > x ) = 0.25
so
p( X < x ) = 0.75
p( x-μ/σ < x-4.6 / 2.9 ) = 75
p( Z < x-4.6 / 2.9 ) = 0.75 ----- 1
also, from the standard normal table; P( Z < 0.67 ) = 0.75 ------ 11
from equation 1 and 11
x-4.6 / 2.9 = 0.67
x-4.6 = 2.9 × 0.67
x - 4.6 = 1.943
x = 4.6 + 1.943
x = 6.543 ≈ 6.5
Therefore, the length of stay is exceeded by 25% of the visits is 6.5 hrs
c) From the normally distributed model, what is the probability of a length of stay less than 0 hours?
P( X < 0 ) = p( x-μ/σ < 0-4.6 / 2.9 )
= P( Z - 1.59)
from table;( Z - 1.59) = 0.0559
P( X < 0 ) = 0.0559
The probability of length of stay less than 0 hours is 0.0559, length of stay cannot be less than 0. When the normal model is used, we assume that the LOF is approximately normally distributed.
The LOF is better modeled by the normal distribution near the mean and worse in the tails.
The probabilities in the left tail for the vales of X < 0 can be neglected.