Complete Question
In a random sample of ten people, the mean driving distance to work was 23.1 miles and the standard deviation was 6.6 miles. Assume the population is normally distributed and use the t-distribution to find the margin of error and construct a 99% confidence interval for the population mean Interpret the results. Identify the margin of error.
Answer:
The 99% confidence interval is [tex]16.32< \mu <29.88[/tex]
The interpretation is that there is 99% confidence that the true mean lies within the limits
The margin of error is [tex]E = 6.783[/tex]
Step-by-step explanation:
From the question we are told that
The sample mean is [tex]\= x = 23.1[/tex]
The standard deviation is [tex]\sigma = 6.6 \ miles[/tex]
The sample size is n = 10
Generally the degree of freedom is mathematically represented as
[tex]df = n-1[/tex]
=> [tex]df = 10-1[/tex]
=> [tex]df =9[/tex]
Given that the confidence level is 99% , the n the level of significance is mathematically evaluated as
[tex]\alpha = 100 - 99[/tex]
[tex]\alpha =1\%[/tex]
[tex]\alpha =0.01[/tex]
Next we obtain the critical value of [tex]\frac{\alpha }{2}[/tex] with a df of 9 from from the student t-distribution table the value is
[tex]t _{\frac{\alpha }{2} , df } = 3.250[/tex]
Generally the margin of error is mathematically represented as
[tex]E = t_{\frac{\alpha }{2} , df } * \frac{\sigma }{\sqrt{n} }[/tex]
[tex]E = 3.250 * \frac{6.6 }{\sqrt{10} }[/tex]
[tex]E = 6.783[/tex]
The 99% confidence interval is
[tex]\= x - E < \mu < \= x + E[/tex]
=> [tex]23.1 - 6.78 < \mu <23.1 + 6.78[/tex]
=> [tex]16.32< \mu <29.88[/tex]
The interpretation is that there is 99% confidence that the true mean lies within the limits
Michelle is 7 years older than her sister Joan, and Joan is 3 years younger than their brother Ryan. If the sum of their ages is 64, how old is Joan?
16
22
18
19
Answer:
(C) 18
Step-by-step explanation:
We can create a systems of equations. Assuming [tex]m[/tex] is Michelle's age, [tex]j[/tex] is Joan's age, and [tex]r[/tex] is Ryan's age, the equations are:
[tex]m = j + 7[/tex]
[tex]j = r-3[/tex]
[tex]m+j+r = 64[/tex]
We can use substitution, since we know the "values" of m and j.
[tex](j+7)+(r-3)+r = 64\\(j+7)+(2r-3)=64\\2r + j + 4 = 64\\2r + j = 60\\\\[/tex]
[tex]r = 21, j = 18[/tex]
So we know that Joan is 18 years old.
Hope this helped!
Which of the following is NOT a requirement of testing a claim about two population means when 1 and 2 are unknown and not assumed to be equal? Choose the correct answer below. A. The two samples are dependent. B. Both samples are simple random samples. C. Either the two sample sizes are large (30 and 30) or both samples come from populations having normal distributions, or both of these conditions are satisfied. D. The two samples are independent.
Answer:
b
Step-by-step explanation:
Which of the following is equal to the rational expression below when x=-1
or -8?
11(x+8)
/(x + 1)(x+8)
Answer:
11/(x + 1) thus d: is the answer
Step-by-step explanation:
Simplify the following:
(11 (x + 8))/((x + 1) (x + 8))
(11 (x + 8))/((x + 1) (x + 8)) = (x + 8)/(x + 8)×11/(x + 1) = 11/(x + 1):
Answer: 11/(x + 1)
1. If a bug can flap its wings at a rate of 92 times in 6 seconds, how many times do they flap their wings in 2.34 minutes? Round to 1 decimal.
Answer:
2152.8
Step-by-step explanation:
First, 2.34 minutes is 140.4 seconds. Next, the bug can flap its wings at a pace of 15.333..... flaps per second. Multiplying this, we get 2152.8
Classify the expression: 5x + 3x^2 − 7x^3 + 2
A. Linear Expression
B. Quadratic Expression C. Cubic Expression
D. Quartic Expression
Answer:
C. Cubic expression.
Step-by-step explanation:
The highest exponent is 3 ( in the term 7x^3) so it is cubic.
Answer:
C. Cubic Expression.
Step-by-step explanation:
5x + 3x^2 - 7x^3 + 2
= 3x^2 - 7x^3 + 5x + 2
= -7x^3 + 3x^2 + 5x + 2
The highest value of exponent in the equation is 3.
For a linear expression, the highest exponent is 1.
For a quadratic expression, the highest exponent is 2.
For a cubic expression, the highest exponent is 3.
For a quartic expression, the highest exponent is 4.
So, this is C. Cubic Expression.
Hope this helps!
Answer two questions about Equations A and B:
A. 2x-1=5x
B. -1=3x
1) How can we get Equation B from Equation A?
Choose 1 answer:
Add/subtract the same quantity to/from both sides
Add/subtract a quantity to/from only one side
Rewrite one side (or both) by
combining like terms
Rewrite one side (or both) using the distributive property
NEXT QUESTION
based on the previous answer, are the equations equivalent? In other words, do they have the same solution?
A. Yes
B. No
Answer:
B: Add/subtract the same quantity to/from both sides
Next Question: Yes
Step-by-step explanation:
thats what the answer is dunno what else to tell you lol
Algebraic equations are mathematical equations that contain unknown variables.
To get Equation B from Equation A, we add/subtract the same quantity to/from both sides. Option A is the correct option. Equation A is equivalent to Equation BQuestion 1: We are given equation A as:2x - 1 = 5x .............Equation A
To get Equation B from A, we would subtract 2x from both sides of the equation.
2x - 2x - 1 = 5x - 2x
- 1 = 3x This is Equation B
Question 2: Based on the previous answer,2x - 1 = 5x is equal to -1 = 3x.
Hence, both Equation A and Equation B are equivalent expressions.
Therefore,
To get Equation B from Equation A, we add/subtract the same quantity to/from both sides. Option A is the correct option.Equation A is equivalent to Equation BTo learn more, visit the link below:
https://brainly.com/question/22299566
What is the slope of the line that goes through the points (-2, 4) and (5, -1)
Answer:
-5/7
Step-by-step explanation:
The slope of a line is given by
m = (y2-y1)/(x2-x1)
= ( -1 -4)/(5 - -2)
= (-1-4)/(5+2)
-5/7
Slope formula: y2-y1/x2-x1
= -1-4/5-(-2)
= -5/7
Best of Luck!
Nicole ordered a volleyball for $9.75
Answer:
the other person is right
you should try putting the WHOLE question
Step-by-step explanation:
Each leg of a 45°-45°-90° triangle measures 12 cm.
What is the length of the hypotenuse?
Z
х
45°
45°
O 6 cm
12 cm
12 cm
O 672 cm
O 12 cm
O 122 cm
Answer:
The legs are 12 cm each, so the hypotenuse is
√(144+144)=12√2
Step-by-step explanation:
Applying the Pythagorean Theorem, the length of the hypotenuse is: 12√2 cm.
The Pythagorean TheoremWhere, a and b are two legs of a right triangle, and c is the hypotenuse, the Pythagorean Theorem states that, c² = a² + b².Given the two legs of the right triangle to be 12 cm
Therefore:c² = 12² + 12².
c² = 288
c = √288
c = 12√2 cm
Therefore, applying the Pythagorean Theorem, the length of the hypotenuse is: 12√2 cm.
Learn more about, the Pythagorean Theorem on:
https://brainly.com/question/654982
Ethan has collected 417 football cards. He shares them equally between himself and his two friends. How many will each person get
Answer:
139 cards
Step-by-step explanation:
This is basically just a division statement - we have 417 cards and want to split it with 3 people (two friends + himself = 3 people).
We can divide these using a calculator or long division, but either way you will get:
[tex]417\div3=139[/tex]
Hope this helped!
Answer: 139
Step-by-step explanation:
417 divided by 3 gives you 139.
Expand $(x+1)(x^{2}+1)(x-1)$. What is the sum of the coefficients of the resulting expression?
Answer:
0
Step-by-step explanation:
Hello, please consider the following.
For any a and b real numbers we can write.
[tex](a-b)(a+b)=a^2-b^2[/tex]
We apply this formula two times here, as below.
[tex](x+1)(x^{2}+1)(x-1)=(x+1)(x-1)(x^{2}+1)\\\\=(x^2-1^2)(x^2+1)=(x^2-1)(x^2+1)\\\\=(x^2)^2-1^2=x^4-1[/tex]
We have the coefficient of 1 for [tex]x^4[/tex] and the constant term is -1, so the sum of the coefficients is 0.
Thank you.
Answer:
1
Step-by-step explanation:
(x + 1)(x² + 1)(x - 1)
= (x³ + x + x² + 1)(x - 1)
= x^4 - x³ + x² - x - x³ - x² + x - 1
= x^4 - 1
Coefficient of x^4 = 1
A slope triangle for line l is shown on the graph below. If the
slope of the line is 4/3 what is the value of w?
Answer:
9
Step-by-step explanation:
What we have to note is that the slope of a line is rise/run. This means that the amount of y change in that line is 4, and the amount of x change is 3.
We can now use a proportion to find the value of w.
[tex]\frac{4}{3} = \frac{12}{x}[/tex]
Cross multiply:
[tex]12\cdot36 = 36\\\\36\div4=9[/tex]
Hope this helped!
Answer: 9
Step-by-step explanation:
can someone help me please
Answer:
[tex] {x}^{4} = 2880[/tex]
Step-by-step explanation:
[tex] {y}^{2} = 20 \: (eq . \: 1)[/tex]
[tex] {x}^{2} = {(2 \sqrt{3y)} }^{2} = 12y [/tex]
Putting value of eq. 1 in the following:
[tex] {x}^{4 } = {(12y)}^{2} = 144{y}^{2} = 144 \times 20 = 2880[/tex]
Suppose that 200 students are randomly selected from a local college campus to investigate the use of cell phones in classrooms. When asked if they are allowed to use cell phones in at least one of their classes, 40% of students responded yes. Using these results, with 95% confidence, the margin of error is 0.068. How would the margin of error change if the sample size increased from 200 to 400 students?
Answer:
It would change to 0.04802
Step-by-step explanation:
from this question we have that n became 400
40% of 400
= 160
p* = 160/400
= 0.4
1 - p* =
= 1 - 0.4
= 0.6
at confidence level,
1 - 0.95
= 0.05
alpha/2 = 0.025
z= 1.96
margin of error. E
= 1.96 x √[(0.4 x 0.6)/400]
= 1.96 x 0.0245
= 0.04802
M.E = 0.04802
tan inverse 1/4 +tan inverse 2/7 = 1/2 cos inverse 3/5
Answer:
The equation is always false
Step-by-step explanation:
arctan1/4+arctan2/7=1/2arccos3/5
0.24497866+0.27829965=1/2(0.92729521)
0.52327832 =0.46364760
not equivalent and will never be.
A spring is hanging from a ceiling. The length L(t) (in cm) of the spring as a function of time t (in seconds) can be modeled by a sinusoidal expression of the form a*sin(b*t) +d. At t=0, when the spring is exactly in the middle of its oscillation, its length is 7 cm. After 0.5 seconds the spring reaches its maximum length, which is 12 cm. Find L(t).
Answer:
L(t) = 5·sin(πt) +7
Step-by-step explanation:
The middle of the oscillation of the given function occurs when t=0. At that point, ...
L(0) = d = 7
The next maximum of the oscillation occurs when the argument of the sine function is π/2.
b·t = π/2
b = π/(2t) = π/(2·0.5) = π
At that maximum, the length is 12, so we have ...
L(0.5) = a·sin(0.5π) +7 = 12
a = 5
The function L(t) is ...
L(t) = 5·sin(πt) +7
Solve for x -3x-3=-3(x+1)
Step-by-step explanation:
[tex] - 3x - 3 = - 3(x + 1) \\ - 3x - 3 = - 3x - 3 \\ - 3x + 3x = - 3 + 3 \\ 0 = 0[/tex]
Step 1: Use 3 to open the bracket
Step 2 : Collect like terms and simplify
Answer = 0
if 2x-7 is 5 more than x+4, what is the value of 3x+5
Answer:
53
Step-by-step explanation:
Let's start with the given relation:
2x -7 = (x+4) +5
x = 16 . . . . . . . . . add 7-x
3x +5 = 3(16) +5 = 53 . . . . . multiply by 3 and add 5
The value of 3x+5 is 53.
7. Suppose that y varies inversely with x. Write an equation for the inverse variation,
y = 4 when x = 6
A
у
x =
2
B
х
y =
24
с
24
y =
OD y = 2x
Answer:
The answer is
[tex]y = \frac{24}{x} [/tex]Step-by-step explanation:
The statement
y varies inversely with x is written as
[tex]y = \frac{k}{x} [/tex]
where k is the constant of proportionality
To find k substitute the values of x and y into the equation
From the question
y = 4
x = 6
We have
[tex]4 = \frac{k}{6} [/tex]
Cross multiply
k = 4 × 6
k = 24
So the formula for the variation is
[tex]y = \frac{24}{x} [/tex]Hope this helps you
Answer: 5
Step-by-step explanation:
One ingot contains 10 kg of pure silver and 2 kg of league. What quantity of silver, whose grade is 0.700; is it necessary to melt to obtain silver with a grade of 0.750?
a) 20
b) 22
c) 16
d) 24
e) 19
Answer:
a) 20
Step-by-step explanation:
If x is the kg of 0.700 grade silver, then:
Silver in ingot + silver in 0.700 alloy = silver in 0.750 alloy
10 + 0.7x = 0.75(x + 12)
10 + 0.7x = 0.75x + 9
1 = 0.05x
x = 20
Need Help
Please Show Work
Answer:
1= 65 degrees
2=115 degrees
3=115 degrees
Step-by-step explanation: supplementary angles where 115 + x = 180 so go backwards by 180 - 115=65 to find corresponding angles. Angle 3 is also corresponding with the given angle of 115. Angle 2 is opposite the 115 so they have to be equal
what is the distance between the points (4 3) and (1 -1) on the cordinate plane
Answer:
d = 5
Step-by-step explanation:
Distance formula: [tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
d = sqrt[(1-4)^2+(-1-3)^2]
d = 5
Answer:
5
Step-by-step explanation:
distance = square root of (1-4)^2 + (-1-3)^2
=> distance = square root of -3^2 + (-4)^2
=> distance = square root of 9 + 16
=> distance = square root of 25
=> distance = 5
Find the area of the irregularly-shaped hexagon below
let each box length be 1
for white triangle
area = ½bh
=½(4)(2)
=4
for orange triangle
area=½(2)(3)
=3
for blue marked boxes
each of the box
area=l²
=(1)²
=1
there are 16 boxes
so the total area will be 16
total area of the hexagon = 4+3+16
=23 square units
[tex]A_1=\dfrac{1}{2}(3+5)\cdot 3=12\\A_2=1\cdot5=5\\A_3=\dfrac{1}{2}(5+1)\cdot 2=6[/tex]
So the area of the whole shape is [tex]12+5+6=23[/tex]
The monthly cost (in dollars) of water use is a linear function of the amount of water used (in hundreds of cubic feet, HCF). The cost for using 15 HCF of water is 32.84, and the cost for using 43 HCF is 79.04. What is the cost for using 36 HCF of water?
Answer:
67.49
Step-by-step explanation:
Let the number of HCF be x.
Let the cost be y.
You are given 2 points of a line: (15, 32.84) and (43, 79.04).
Now we find the equation of the line that passes through those points.
y - y1 = m(x - x1)
y - 32.84 = [(79.04 - 32.84)/(43 - 15)](x - 15)
y - 32.84 = (46.2/28)(x - 15)
y - 32.84 = 1.65(x - 15)
y = 1.65x - 24.75 + 32.84
y = 1.65x + 8.09
Now we let x = 36 and solve for y.
y = 1.65(36) + 8.09
y = 67.49
Please help answer the following questions!!! :D I will do anything in return!
Julissa gave out an equal number of oranges to each of the 6 apartments on her floor. if she gave each apartment 5 oranges, how many oranges did Julissa give out in all?
julissa gave equal oranges in 6 apartments
she gave each apartment 5 oranges
so total no. of oranges are = 6×5 = 30
Answer:
D. 30
Step-by-step explanation:
Jaclyn is one-fourth of a foot taller than John. John is 31/6 feet tall. How many feet tall is Jaclyn
Answer:
5 5/12
Step-by-step explanation:
31/6 feet + 1/4 foot
= 31/6 + 1/4
= [(31 * 4) / 6 * 4] + [(1 * 6) / 4 * 6]
= [ 124/24 ] + [ 6/24 ]
= (124 + 6) / 24
= 130 / 24
= 5 10/24
= 5 5/12
Hope this helps! Tell me if I'm wrong!
Find f(x) and g(x) so the function can be expressed as y = f(g(x)). y= [tex]\frac{2}{x^2}[/tex]+3
Answer:
One possible answer is:
f(x) = (2/x) + 3 and g(x) = x².
Step-by-step explanation:
Explanation:
We are to write this equation as y = f(g(x)). This means we want it to be a composite of functions; in f(x), we take the value of g(x) and use in place of x.
If we let g(x) = x², this means everywhere we see an x in f(x), we will replace it with x². To make our equation y = 2/x² + 3, working backward we would substitute x for x²; this would give us f(x) = 2/x + 3.
Which relation is a function?
The number two is a function
First rule of function: for each element of A there is one and only one element of B
For example, in the first one -5 is "collegated" to -2 and 3. So this isn't a function.
Naturally, every element of B can have more element of A
A homeowner wants to build a fence to enclose a 320 square yard rectangular area in his backyard. Along one side the fence is to be made of heavy-duty material costing $9 per yard, while the material along the remaining three sides costs $1 per yard. Determine the least cost to the homeowner.
Answer:
Determination of the least cost of fence enclosure:
= cost of heavy-duty one side of the length plus cost of remaining three sides of the fence
= $416 ($360 + $56)
= $416
Step-by-step explanation:
Rectangular Fence Area = 320 square yard
Since fence is rectangular, the two sides are length and width
Length of rectangular is always greater than the width
Length cannot be 20 yard with width as 16 yard
Therefore, length = 40 yard and width = 8 yard.
Proof: Area of a rectangular = 40 x 8 = 320 square yard
Since, parameter = 2 (Length + Width)
= 2 x (40 + 8)
= 96 yards
Therefore, along one side with heavy-duty material is one length side of the fence = 40 yard
Cost of the one length with heavy-duty material = 40 x $9 = $360
Remaining three sides = 96 - 40 = 56 yard
Cost of remaining three sides = 56 x $1 = $56
Total cost of fencing = $416 ($360 + $56)
