Answer:
3.27 hours
Step-by-step explanation:
Calculate the difference in speed and distance between the trains.
The relative speed:
101 - 90 = 11 mph
Difference in distance:
42 - 6 = 36 miles
[tex]time=\frac{distance}{speed}[/tex]
[tex]t=\frac{36}{11}[/tex]
[tex]t = 3.27[/tex]
Answer:
yeah she is correct
Step-by-step explanation:
Solve the following system of equations. Express your answer as an ordered pair in the format (a,b). 3x+4y=17 -4x-7y=-18
Answer:
Step-by-step explanation:
3x+4y = 17 _______ equation 1
-4x -7y= -18 _______ equation 2
muliply by 4 in equation 1
12x + 16y = 68 ______ equation 3
multiply by 3 in equation 2
-12x - 21y = -54 ________ equation 4
add equation 3 & 4
- 5y = 14
y = - 14/5
substitute y in equation 1
3x + 4 (-14/5) =17
3x = 17+ (56/5)
3x =( 85 + 56) / 5
3x = 141/5
x = 47/5
hence (a,b) = (47/5, -14/5)
Independent random samples taken on two university campuses revealed the following information concerning the average amount of money spent on textbooks during the fall semester.
University A University B
Sample Size 50 40
Average Purchase $280 $250
Standard Deviation $20 $23
At 95% confidence test to determine if, on the average, students at University A spend more on textbooks then the students at University B.
Answer:
Z > Zα
6.511 > 1.645
Step-by-step explanation:
University A University B
Sample Size 50 40
Average Purchase $280 $250
Standard Deviation $20 $23
We formulate
H0: x1` > x2` null hypothesis that the mean of the University A is greater than the mean of the University B
HA: x1`≤ x2` one tailed test
Test statistic
Z= x1`-x2`/ √s₁²/n₁ +s²₂/n₂
Z= 280-250/√400/50 + 529/40
Z= 30/√8 +13.225
Z= 30 /4.607
Z= 6.511
For one tailed test at α= 0.05 = 1.645
Z > Zα
6.511 > 1.645
Thus we reject null hypothesis.On the average, students at University A spend more on textbooks then the students at University B.
Please answer this correctly without making mistakes my work is due today
Answer:
24.24
Step-by-step explanation:
brainlist plzzzzzzzzzzz
16. Use yesterday’s stock table for the company Icarus to answer the following questions.
52-week Price
High Low
Stock
Symbol
Dividend
Annual Yield Return (%)
P/E ratio
Volume Traded
High Low
Price Price
Closing Price
Net Change
28.38 15
Icarus
ICR
0.41
1.1
24
105300
24 23.5
24
. . . .
a. What was the high price for Icarus stock over the last 52 weeks?16a. _______________
b. If you owned 1000 shares of Icarus stock last year, what is the dollar amount of the b. _________________
dividend you received?
c. What is the annual yield return for dividends alone?c. _________________
d. How many shares of Icarus stock were traded yesterday?d. _________________
e. What was the low price for Icarus stock yesterday?e. _________________
f. What was the price of Icarus stock at the close of the stock exchange yesterday?f. _________________
g. Compute Icarus’s annual earnings per share using the formula below.g. _________________
What is the y-intercept of the function f(x)=4 - 5x?
-5
-4
4
5
Answer:
y-intercept = (0,4)
Step-by-step explanation:
To find the y-intercept, the place at which the value of x is 0, simply plug zero into your function:
f(x) = 4 - 5x
f(0) = 4 - 5(0)
f(0) = 4
Hence, the y-intercept occurs at (0,4).
The y-intercept of f(x) = 4 - 5x is 4.
Using the slope intercept formula the y-intercept can be found below
y = mx + bwhere
m = slope
b = y-intercept
From the equation:
f(x) = 4 - 5x
According to the slope intercept format,
m = slope = -5
y- intercept = 4
Therefore, the y-intercept of f(x) = 4 - 5x is 4.
read more: https://brainly.com/question/4023516?referrer=searchResults
Professor Easy's final examination has 9 true-false questions followed by 3 multiple-choice questions. In each of the multiple-choice questions, you must select the correct answer from a list of five. How many answer sheets are possible? choices
Answer: 2⁹5³ = 64,000
Step-by-step explanation:
There are 9 questions with 2 options (true or false) = 2⁹
There are 3 multiple questions with 5 options = 5³
true/false questions AND multiple choice questions
2⁹ x 5³ = 2⁹5³
The formula to convert Fahrenheit to Celsius is C=5/9(F-32). Convert 30c to Fahrenheit. Round to the nearest degree
Answer:
86 degrees farenheit
Step-by-step explanation:
First, we plug 30 in for C.
Next, solve for F
Multiplying both sides by 9/5 gives us 54=F-32
Add 32 to both sides 86=F
Find the exact perimeter (in inches) and area (in square inches) of the segment shown, given that m∠O = 60° and OA = 24 in.
Answer:
A. Perimeter of segment = 49 in.
B. Area of segment = 52 in².
Step-by-step explanation:
Data obtained from the question include:
Radius (r) = 24 in.
Angle at the centre (θ) = 60°
Perimeter of segment =.?
Area of segment =.?
A. Determination of the perimeter of the segment.
Perimeter of segment = length of arc + length of chord
Length of arc = θ/360 x 2πr
Length of chord = 2r x sine (θ/2)
Pi (π) = 3.14
Length of arc = θ/360 x 2πr
Length of arc = 60/360 x 2 x 3.14 x 24
Lenght of arc = 25.12 in
Length of chord = 2r x sine (θ/2)
Length of chord = 2 x 24 x sine (60/2)
Length of chord = 24 in
Perimeter of segment = length of arc + length of chord
Perimeter of segment = 25.12 + 24
Perimeter of segment = 49.12 ≈ 49 in.
B. Determination of the area of the segment.
Area of segment = Area of sector – Area of triangle.
Area of sector = θ/360 x πr²
Area of triangle = r²/2 sine θ
Area of sector = θ/360 x πr²
Area of sector = 60/360 x 3.14 x 24²
Area of sector = 301.44 in²
Area of triangle = r²/2 sine θ
Area of triangle = 24²/2 x sine 60
Area of triangle = 249.42 in².
Area of segment = Area of sector – Area of triangle.
Area of segment = 301.44 – 249.42
Area of segment = 52.02 ≈ 52 in²
If ABC=DEC B=48 and E=C+4
x=?
Answer:44
Step-by-step explanation:the two triangles are congruent , so we deduce from that the angle B=angle E =48
So, x+4=48 , x=44 degree
Find the indicated binomial probability. A multiple choice test has 30 questions, and each has four possible answers, of which one is correct. If a student guesses on every question, find the probability of getting exactly 12 correct.
Answer:
0.02906
Step-by-step explanation:
number of questions =30
getting exactly right : 12
30C12 the number of possibilities
probability to get it right (1/4)^12
probability of failure =1-1/4=(3/4)^18 ( 18 = 30 questions -12 right )
P(12)=30C12*(1/4)^12*(3/4)^18=0.02906
hope it helps
The volume of a cylinder varies jointly with the base (area) and the height. The volume is 40 inches^3 when the base (area) is 6 inches^2 and the height is 20 inches. Find the volume of the cylinder (after finding the variation constant) when the base (area) is 8 inches^2 and the height is 12 inches.
Answer: K = ¹/₃, V = 32in³
Step-by-step explanation:
Volume of s cylinder (V) = πr²h where πr² is the base area.
Now from the question,
V ∞ πr²h
V = kπr²h where k is the constant of proportionality which is also the variation constant.
40 = 6 x 20 x k
40 = 120k and
k = ⁴⁰/₁₂₀
= ¹/₃.
Now to find the volume when base area is 8in² and h is 12,
V = 8 x 12 x ¹/₃
V = 32in³
2. Compare the function ƒ(x) = –x^2 + 4x – 5 and the function g(x), whose graph is shown. Which function has a greater absolute maximum (vertex)?
Answer:
g(x)
Step-by-step explanation:
The vertex of g(x) as shwon in the graph is located in the point wich coordinates are (3.5,6.25) approximatively
We need to khow the coordinates of f(x) vertex
Here is a way without derivating:f(x) = -x² + 4x -5
let a be the leading factor, b the factor of x and c the constant:
a= -1b= 4c= -5The coordinates of a vertex are: ([tex]\frac{-b}{2a}[/tex] , f([tex]\frac{-b}{2a}[/tex]) )
-b/2a = -4/ (-1*2) = 4/2 = 2
f(2)= -2²+4*2-4 = -4+4-4 = -4
obviosly f(x) has a minimum wich less than g(x)'s maximum
Answer:
Step-by-step explanation:
g(x) i think
An engineer is going to redesign an ejection seat for an airplane. The seat was designed for pilots weighing between 130 lb and 171 lb. The new population of pilots has normally distributed weights with a mean of 138 lb and a standard deviation of 34.9 lb.
a. If a pilot is randomly selected, find the probability that his weight is between 150 lb and 201 lb.
b. If 39 different pilots are randomly selected, find the probability that their mean weight is between 150 lb and 201 lb.
c. When redesigning the ejection seat which probability is more relevant?
Answer:
The answer is below
Step-by-step explanation:
Given that:
mean (μ) = 138 lb, standard deviation (σ) = 34.9 lb
z score is used in statistic to determine by how many standard deviations the raw score is above or below the mean. It is given by:
[tex]z=\frac{x-\mu}{\sigma}[/tex]
a) For probability that his weight is between 150 lb and 201 lb, we need to calculate the z score for 150 lb and for 201 lb.
For 150 lb:
[tex]z=\frac{x-\mu}{\sigma}=\frac{150-138}{34.9}=0.34[/tex]
For 201 lb:
[tex]z=\frac{x-\mu}{\sigma}=\frac{201-138}{34.9}=1.81[/tex]
From normal distribution table, probability that his weight is between 150 lb and 201 lb = P(150 < x < 201) = P(0.34 < z < 1.81) = P(z < 1.81) - P(z < 0.34) = 0.9649 - 0.6331 = 0.3318 = 33.18%
b) If 39 different pilots are randomly selected i.e. n = 39. For probability that his weight is between 150 lb and 201 lb, we need to calculate the z score for 150 lb and for 201 lb.
For 150 lb:
[tex]z=\frac{x-\mu}{\sigma/\sqrt{n} }=\frac{150-138}{34.9/\sqrt{39} }=2.15[/tex]
For 201 lb:
[tex]z=\frac{x-\mu}{\sigma/\sqrt{n} }=\frac{201-138}{34.9/\sqrt{39} }=11.3[/tex]
From normal distribution table, probability that his weight is between 150 lb and 201 lb = P(150 < x < 201) = P(2.15 < z < 11.3) = P(z < 11.3) - P(z < 2.15) = 1 - 0.9842 = 0.0158 = 1.58%
c) The probability from part C is more important
Simplify the following algebraic expression.
square root of 39x^7
Answer: x^3 square root 39x
Step-by-step explanation:
Simplify the radical by breaking the radicand up into a product of known factors, assuming positive real numbers.
Consider the expression 8 – 4 / 2. One student says the answer is 2 and another says it is 6. Which student is correct? Explain what went wrong with the student who made a mistake.
Answer:
It is 6. The student who got a two did not use order of operations.
Step-by-step explanation:
PEMDAS
You must do division before subtraction. 4/2 = 2.
8 - 2 = 6
Find x.................
Answer:
90°
Step-by-step explanation:
Theres a right angke beside x
And Angles on a straight line = 180 so 180-90°= 90°
Answer:
90
Step-by-step explanation:
I looked it up on the internet
6th grade math, help me please:)
Answer:
8:3 is the ratio of kids to adults
32 kids, so there are 12 adults
Answer:
32 kids to 4 adults
Step-by-step explanation:
1st row- 8 kids to 3 adults
2nd row- 16 kids to 6 adults
3rd row- 24 kids to 9 adults
4th row- 32 kids to 12 adults
You visit a farm and notice that white chickens lay white eggs and colored chickens lay colored eggs, so you decide that only white chickens lay white eggs. What type of reasoning is this?
Answer:
This is called an Inductive reasoning.
Step-by-step explanation:
It is a logical process in which a number of premises all believed true combine to come up with specific conclusions. This is a generalisation based on observations.
Hope it helps.
All sides of the building shown above meet at right angles. If three of the sides measure 2 meters, 7 meters, and 11 meters as shown, then what is the perimeter of the building in meters?
Answer:
Perimeter= 40 units
Step-by-step explanation:
Ok
We are asked to look for the perimeter.
We have some clue given.
All at right angle and some sides are given it's full length.
We have the bae to be 11 unit
The height to be 7 unit.
What this mean is that taking either the base or the height should sum up to either 11 or 7 respectively.
Let's go for the other side of the height.
Let's take all the vertical height and sum it up to 7 because the right side is equal to 7.
So we have 7+7+11
But it's not complete yet.
We are given a dimension 2.
And the 2 is in two places so it's total 2*2= 4
The two is for a small base .
The base is actually an extra to the 11 of the other base.
So summing up
We have 2*11 + 2*7 + 2*2
Perimeter= 22+14+4
Perimeter= 40 units
A manufacturer claims that its rechargeable batteries are good for an average of more than 1.000 charges. A random sample of 100 batteries has a mean life of 1002 charges and a standard deviation of 14. Is there enough evidence to support this claim at a significance level of 0.01?
a. State the hypotheses.
b. State the test statistie information
c. State either the p-value or the critical information d. State your conclusion and explain your reasoning
It's 1000 charges and not 1.000 charges
Answer:
A)Null Hypothesis;H0: μ = 1000
Alternative Hypothesis;Ha: μ ≠ 1000
B) t-statistic = 1.4286
C) p-value = 0.15628
D) We conclude that we will fail to reject the manufacturers claim that its rechargeable batteries are good for an average of more than 1000 charges
Step-by-step explanation:
We are given;
x = 1002 charges
s = 14
μ = 1000 charges
n = 100
degree of freedom = n - 1 = 100 - 1 = 99
A) The hypotheses are;
Null Hypothesis;H0: μ = 1000
Alternative Hypothesis;Ha: μ ≠ 1000
B) t-statistic = (x - μ)/(s/√n)
(1002 - 1000)/(14/√100) = 1.4286
C) From the t-score calculator results attached, the p-value is approximately 0.15628
D) The P-value of 0.15628 is is greater than the significance level of 0.01, thus we fail to reject the null hypothesis, and we conclude that the result is statistically nonsignificant.
An oil company is interested in estimating the true proportion of female truck drivers based in five southern states. A statistician hired by the oil company must determine the sample size needed in order to make the estimate accurate to within 2% of the true proportion with 99% confidence. What is the minimum number of truck drivers that the statistician should sample in these southern states in order to achieve the desired accuracy?
Answer: n = 2401
Step-by-step explanation:
Given;
Confidence level = 2% - 99%
n = ? ( which is the sample size is unknown ).
Solution:
Where;
n = [z/E]^2*pq
Since no known value for ( p ) estimate is given, the "least biased" estimate is p = 1/2
Substituting the given data into the formula.
n = [1.96/0.02]^2(1/2)(1/2)
n = 2401
The minimum number of truck drivers the statistician needs to sample for an accurate result is 2401
Please show step by step working out of stationary points and points of inflection with the y coordinates (and sketch graph) for the equation y=x^4-36x^2
Answer:
See picture attached
Step-by-step explanation:
2/3x + 5 = 3 plz helppppppp
Answer:
2 /3 +5 = 3
5.666667≠3
False
Step-by-step explanation:
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Hi my lil bunny!
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Lets do this step by step.
~~~~~~~~~~~~~~~~~~~~
Multiply both sides of the equation by [tex]\frac{3}{2}[/tex] .
[tex]\frac{3}{2} . \frac{2}{3} . x = \frac{3}{2} . 5[/tex]
Simplify both sides of the equation.
~~~~
Simplify [tex]\frac{3}{2} . \frac{2}{3} . x .[/tex]
[tex]x = \frac{3}{2} . 5[/tex]
Multiply [tex]\frac{3}{2} . 5[/tex]
[tex]x = \frac{15}{2}[/tex]
The result can be shown in multiple forms.
Exact Form: [tex]x = \frac{15}{2}[/tex]
Decimal Form: [tex]x = 7.5[/tex]
Mixed Number Form: [tex]x = 7\frac{1}{5}[/tex]
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Hope this helped you.
Could you maybe give brainliest..?
❀*May*❀
SCREENSHOT OF MY QUESTION:
Answer in fraction form = 9/8
Answer in decimal form = 1.125
note: the improper fraction 9/8 converts to the mixed number 1 & 1/8
To get this answer, we divide both sides by 8 to isolate n. The expression 8n really means "8 times n". We divide to undo the multiplication.
Helppppp............
Answer:
A (15/16)
D (0.45)
E (1/14)
F (0)
Step-by-step explanation:
Allowable values for probabilities (p) are numbers greater than or equal to zero and smaller than or equal to one:
[tex]0\leq p\leq 1[/tex]
Therefore you can select answers:
A (15/16)
D (0.45)
E (1/14)
F (0)
Answer:
0, 1/2, 0.1, 15/16 are the answers
Step-by-step explanation: I don't think negative numbers count as a probability
Use cylindrical shells to find the volume of the solid generated when the region enclosed by the given curves is revolved about the y-axis.
y=x³,
x=1,
y=0
Each shell has radius [tex]x[/tex] and height [tex]x^3[/tex], so the volume of this solid is
[tex]\displaystyle2\pi\int_0^1x^4\,\mathrm dx=\boxed{\frac{2\pi}5}[/tex]
I toss an unfair coin 12 times. This coin is 65% likely to show up heads. Calculate the probability of the following.
a. 11 heads:
b. 2 or more heads:
c. 7 heads:
d. 9 tails:
e. 8 or less heads:
Answer:
a. 0.0368
b. 0.99992131
c. 0.2039
d. 0.0048
e. 0.6533
Step-by-step explanation:
Let the probability of obtaining a head be p = 65% = 13/20 = 0.65. The probability of not obtaining a head is q = 1 - p = 1 -13/20 = 7/20 = 0.35
Since this is a binomial probability, we use a binomial probability.
a. The probability of obtaining 11 heads is ¹²C₁₁p¹¹q¹ = 12 × (0.65)¹¹(0.35) = 0.0368
b. Probability of 2 or more heads P(x ≥ 2) is
P(x ≥ 2) = 1 - P(x ≤ 1)
Now P(x ≤ 1) = P(0) + P(1)
= ¹²C₀p⁰q¹² + ¹²C₁p¹q¹¹
= (0.65)⁰(0.35)¹² + 12(0.65)¹(0.35)¹¹
= 0.000003379 + 0.00007531
= 0.0007869
P(x ≥ 2) = 1 - P(x ≤ 1)
= 1 - 0.00007869
= 0.99992131
c. The probability of obtaining 7 heads is ¹²C₇p⁷q⁵ = 792(0.65)⁷(0.35)⁵ = 0.2039
d. The probability of obtaining 7 heads is ¹²C₉q⁹p³ = 220(0.65)³(0.35)⁹ = 0.0048
e. Probability of 8 heads or less P(x ≤ 8) = ¹²C₀p⁰q¹² + ¹²C₁p¹q¹¹ + ¹²C₂p²q¹⁰ + ¹²C₃p³q⁹ + ¹²C₄p⁴q⁸ + ¹²C₅p⁵q⁷ + ¹²C₆p⁶q⁶ + ¹²C₇p⁷q⁵ + ¹²C₈p⁸q⁴
= = ¹²C₀(0.65)⁰(0.35)¹² + ¹²C₁(0.65)¹(0.35)¹¹ + ¹²C₂(0.65)²(0.35)¹⁰ + ¹²C₃(0.65)³(0.35)⁹ + ¹²C₄(0.65)⁴(0.35)⁸ + ¹²C₅(0.65)⁵(0.35)⁷ + ¹²C₆(0.65)⁶(0.35)⁶ + ¹²C₇(0.65)⁷(0.35)⁵ + ¹²C₈(0.65)⁸(0.35)⁴
= 0.000003379 + 0.00007531 + 0.0007692 + 0.004762 + 0.01990 + 0.05912 + 0.1281 + 0.2039 + 0.2367
= 0.6533
The process of producing pain-reliever tablets yields tablets with varying amounts of the active ingredient. The manufacturer claims each tablet has at least 200 milligrams of the active ingredient. The consumer Watchdog Bureau assumes the manufacturer claim is correct, but occasionally tests samples of the tablets to ensure they contain enough of the ingredient. The Consumer Watchdog Bureau tests a random sample of 70 tablets. The sample mean content of the active ingredient is 205.7 milligrams, while the sample standard deviation is 21 milligrams. What is the p-value for this test?
Answer:
The p-value is [tex]p-value = 0.013167[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu[/tex] = 200 milligrams
The sample size is [tex]n = 70[/tex]
The sample mean is [tex]\= x = 205.7[/tex]
The sample standard deviation is [tex]\sigma = 21 \ milligram[/tex]
Generally the Null hypothesis is mathematically represented as
[tex]H_o : \mu = 200[/tex]
The Alternative hypothesis is
[tex]H_a : \mu < 200[/tex]
The test statistics is mathematically represented as
[tex]t_s = \frac{\= x - \mu }{\frac{\sigma}{\sqrt{n} } }[/tex]
substituting values
[tex]t_s = \frac{ 205.7 - 200 }{\frac{21}{\sqrt{70} } }[/tex]
[tex]t_s = 2.270[/tex]
Now the p-value is mathematically represented as
[tex]p-value = P(Z \le t_s )[/tex]
substituting values
[tex]p-value = P(Z \le 2.270 )[/tex]
Using the Excel function[=NORMDIST(2.270)] to calculate the p-value we obtain that
[tex]p-value = 0.013167[/tex]
Answer:
A) 0.012
From CollegeBoard
10. Here is a list of 25 scores on a Math midterm exam: 38.5, 41.5, 52, 52.5, 61, 63, 63.5, 68, 69, 69, 78.5, 79, 80, 83, 87, 88.5, 88.5, 91, 91.5, 92, 92.5, 94, 94, 97, 97 Find P36:
Answer:
69
Step-by-step explanation:
Since the values in the data set has been ranked already from smallest to largest, as shown in the question.
Then calculate the index,
To find the 36th percentile using the data set,
Multiply k (36/100) by n (25) to reach an index of 9.
Then since the index is whole number,
To calculate percentile according to the 'greater than' method, count the values in the data set from smallest to largest until you reach the number ranked 9th
Which is 69.
Since the value for the 36th percentile must be greater than the first nine values, the 10th ranked value would be the kth (36th) percentile. In this data set, that value is 69.
Alternatively, using the 'greater than or equal to' method, after getting the 9th rank,
Include the ninth-ranked value, (69) in this data set.
The kth (36th) percentile is then calculated by taking the average of that value in the data set (69) and the next ranked value (69). (59 + 69) / 2 = 69.
We draw a random sample of size 25 from a normal population with variance 2.4. If the sample mean is 12.5, what is a 99% confidence interval for the population mean?
Answer:
11.2≤[tex]\mu[/tex]12.8Step-by-step explanation:
Confidence interval for the population mean is expressed by the formula;
CI = xbar ± Z(S/√n) where;
xbar is the sample mean = 12.5
Z is the z score at 99% confidence = 2.576
S is the standard deviation = √variance
S = √2.4 = 1.5492
n is the sample size = 25
Substituting the given values into the formula given above,
CI = 12.5 ± 2.576(1.5492/√25)
CI = 12.5 ± 2.576(0.30984)
CI = 12.5 ± 0.7981
CI = (12.5-0.7981, 12.5+0.7981)
CI = (11.2019, 12.7981)
Hence the 99% confidence interval for the population mean is 11.2≤[tex]\mu[/tex]12.8 (to 1 decimal place)
A 99% confidence interval for the population mean will be "11.2 [tex]\leq[/tex] 12.8".
StatisticsAccording to the question,
Sample mean, [tex]\bar x[/tex] = 12.5
Z score at 99%, Z = 2.576
Standard deviation, S = √Variance
= √2.4
= 1.5492
Sample size, n = 25
We know the formula,
Confidence interval, CI = [tex]\bar x \ \pm[/tex] Z ([tex]\frac{S}{\sqrt{n} }[/tex])
By substituting the given values, we get
= 12.5 [tex]\pm[/tex] 2.576 ([tex]\frac{1.5492}{\sqrt{25} }[/tex])
= 12.5 [tex]\pm[/tex] 2.576 (0.30984)
= 12.5 [tex]\pm[/tex] 0.7981
Now,
Cl = (12.5 - 0.7981, 12.5 + 0.7981)
= (11.2019, 12.7981) or,
= (11.2, 12.8)
Thus the above answer is appropriate.
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