An investigator compares the durability of two different compounds used in the manufacture of a certain automobile brake lining. A sample of 71 brakes using Compound 1 yields an average brake life of 41,628 miles. A sample of 31 brakes using Compound 2 yields an average brake life of 36,379 miles. Assume the standard deviation of brake life is known to be 4934 miles for brakes made with Compound 1 and 4180 miles for brakes made with Compound 2. Determine the 98% confidence interval for the true difference between average lifetimes for brakes using Compound 1 and brakes using Compound 2. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval.
Answer:
98% Confidencce Interval is ( 3030.6, 7467.4 )
Step-by-step explanation:
Given that:
Sample size [tex]n_1 =[/tex] 71
Sample size [tex]n_2 =[/tex] 31
Sample mean [tex]\overline x_1 =[/tex] 41628
Sample mean [tex]x_2 =[/tex] 36,379
Population standard deviation [tex]\sigma_1[/tex] = 4934
Population standard deviation [tex]\sigma_2 =[/tex] 4180
At 98% confidence interval level, the level of significcance = 1 - 0.98 = 0.02
Critical value at [tex]z_{0.02/2} = 2.33[/tex]
The Margin of Error = [tex]z \times \sqrt{\dfrac{\sigma_1^2}{n_1}+\dfrac{\sigma^2_2}{n_2} }[/tex]
= [tex]2.33 \times \sqrt{\dfrac{4934^2}{71}+\dfrac{4180^2}{31} }[/tex]
= [tex]2.33 \times \sqrt{\dfrac{24344356}{71}+\dfrac{17472400}{31} }[/tex]
= [tex]2.33 \times \sqrt{906504.06 }[/tex]
= 2218.40
The Lower limit = [tex]( \overline x_1 - \overline x_2) - (Margin \ of \ error)[/tex]
= ( 41628 - 36379 ) - ( 2218.40)
= 5249 - 2218.40
= 3030.6
The upper limit = [tex]( \overline x_1 - \overline x_2) + (Margin \ of \ error)[/tex]
= ( 41628 - 36379 ) + ( 2218.40)
= 5249 + 2218.40
= 7467.4
∴ 98% Confidencce Interval is ( 3030.6, 7467.4 )
Speed limit signs are placed every 58 mi on the highway. How many signs are there on a 75 mi stretch of highway? Which operation should be used to solve the problem? division multiplication
Answer:
you should use multiatication
Step-by-step explanation:
Answer:
lol u got the answer it's multiplication i need POOOIIIIINNNNTTTTSSS
Step-by-step explanation:
How hard is 6th grade math?
Answer:
super easy i can help you whenever
Step-by-step explanation:
im in high and i had As in 6th
Answer:
a little hard you just have to understand it
Step-by-step explanation:
What is one equivalent ratio for 1/3
Answer: 2/6
Step-by-step explanation:
Answer:
[tex]\frac{2}{6}[/tex]
Step-by-step explanation:
In order to create an equal ratio to [tex]\frac{1}{3}[/tex], we need to find a constant to multiply both the numerator and the denominator by.
Let's do 2.
[tex]1\cdot 2 = 2\\\\3\cdot 2 = 6\\\\[/tex]
So:
[tex]\frac{2}{6}[/tex]
Hope this helped!
Solve the equation t+ 25 =26
Answer:
t = 1
Step-by-step explanation:
t + 25 = 26
Subtract 25 from each side
t = 1
Enter the mixed number as a decimal 3 and 1 over 10
whats - 1/64 as cubed
Answer: 1/4
Step-by-step explanation:
NASA launches a rocket at t = 0 seconds. Its height, in meters above sea-level, as a function of time is given by h(t) = -4.9t^2 + 148 t + 227. Assuming that the rocket will splash down into the ocean, at what time does splashdown occur? The rocket splashes down after 32 seconds. How high above sea-level does the rocket get at its peak? The rocket peaks at meters above sea-level.
Answer:
A.) 24.08 seconds
B.) 825.42 metres
Step-by-step explanation:
function of time is given as
h ( t ) = − 4.9 t 2 + 118 t + 115 .
Where a = -4.9, b = 118, c = 115
Let's assume that the trajectory of the rocket is a perfect parabola.
The time t the rocket will reach its maximum height will be at the symmetry of the parabola.
t = -b/2a
Substitute b and a into the formula
t = -118/-2(4.9)
t = 118/9.8
t = 12.041 seconds
Since NASA launches the rocket at t = 0 seconds, the time it will splash down into the ocean will be 2t.
2t = 2 × 12.041 = 24.08 seconds
Therefore, the rocket splashes down after 24.08 seconds.
B.) At maximum height, time t = 12.041s
Substitute t for 12.041 in the function
h ( t ) = − 4.9 t 2 + 118 t + 115
h(t) = -4.9(12.041)^2 + 118(12.041) + 115
h(t) = -4.9(144.98) + 118(12.041) + 115
h(t) = -710.402 + 1420.82 + 115
h(t) = 825.42 metres
Therefore, the rocket get to the peak at 825.42 metres
Help please thanks.
Answer:
Step-by-step explanation:
[tex]\sqrt{1}[/tex] -2 / 6 = (1-2)/6= -1/6= .2 (rounded to tenth)
help me please. 15 POINTS BRAINLEST ANSWER EVER (y+4)–(y–1)=6y
Answer:
5/6
Step-by-step explanation:
y+4-y+1=6y
5=6y
y=5/6
Solution for (y+4)-(y-1)=6y equation:
Simplifying
(y + 4) + -1(y + -1) = 6y
Reorder the terms:
(4 + y) + -1(y + -1) = 6y
Remove parenthesis around (4 + y)
4 + y + -1(y + -1) = 6y
Reorder the terms:
4 + y + -1(-1 + y) = 6y
4 + y + (-1 * -1 + y * -1) = 6y
4 + y + (1 + -1y) = 6y
Reorder the terms:
4 + 1 + y + -1y = 6y
Combine like terms: 4 + 1 = 5
5 + y + -1y = 6y
Combine like terms: y + -1y = 0
5 + 0 = 6y
5 = 6y
Solving5 = 6y
Solving for variable 'y'.Move all terms containing y to the left, all other terms to the right.
Add '-6y' to each side of the equation.
5 + -6y = 6y + -6y
Combine like terms: 6y + -6y = 0
5 + -6y = 0
Add '-5' to each side of the equation.
5 + -5 + -6y = 0 + -5
Combine like terms: 5 + -5 = 0
0 + -6y = 0 + -5
-6y = 0 + -5
Combine like terms: 0 + -5 = -5
-6y = -5
Divide each side by '-6'.
y = 0.8333333333
Simplifying
y = 0.8333333333
A small pebble has a mass of
about
20 L
b.
20 ml
20 g
20 kg
d.
Answer:
20g
since mass should be in kg or gram if small then g
AN = 16CM; AC = 18CM & CN = (4X -6) CM. Find the value of X
Answer:
x = 6
Step-by-step explanation:
Since <A is congruent to <N, they are both an isosceles base angles. ∆CAN is an isosceles ∆.
Therefore, one of the properties of an isosceles ∆ is that two sides are equal, aside the base of the isosceles. This implies that: CN = AC
AC = 18cm
CN = (4x - 6)cm, therefore, we can generate an equation for solve for x as follows,
4x - 6 = 18 (two sides of an isosceles ∆ are congruent)
Add 6 to each side of the equation.
4x - 6 + 6 = 18 + 6
4x = 24
Divide both sides by 4
4x = 24/4
x = 6
3) At a barbecue, there are 68 hotdogs being grilled, and there are 34 people. How many hotdogs does each person get? (You can use a calculator) 68 II 8 Hotdogs People 34 Answer: hotdogs for each person
Answer:
2 hotdogs for each person
Step-by-step explanation:
Use function notation to represent the average speed of the car on the interval from t = 2 to t = 7 .
Answer:
[tex]Average\ Speed = \frac{s(7) - s(2)}{5}[/tex]
Step-by-step explanation:
Given
t = 2 to 7
Required
Find the average speed over these intervals
The function is not given; so, I'll represent the function as s(t)
When [tex]t = 2;[/tex]
[tex]s(t)= s(2)[/tex]
When [tex]t = 7[/tex]
[tex]s(t) = s(7)[/tex]
[tex]Average\ Speed = \frac{Change\ in\ Distance}{Change\ in\ Time}[/tex]
This gives:
[tex]Average\ Speed = \frac{s(7) - s(2)}{7 - 2}[/tex]
[tex]Average\ Speed = \frac{s(7) - s(2)}{5}[/tex]
What is the translation for this graph? O (X-4, Y-3)
O (X-3. y - 4)
O (X-3. y. 4)
O (X- 4. y-3)
Answer:
wow dis might take a while to solve
What is the number of solutions in this system?
one solution
no solution
infinitely many solutions
First answer is Brainlyist
Crude oil Imports to one country from another for 2009-2013 could be approximated by the following model where t is time in years since the start of 2000,
(1) --33428001 - 1,000 thousand barrels per day (9 st s 13)
According to the model, approximately when were oil imports to the country greatest? HINT (See Example 1) (Round your answer to two decimal places.)
How many barrels per day were imported at that time? (Round your answer to two significant digits.)
thousand barrels
Answer:
Time = approximately mid 2012Oil import rate = 3600 barrelsStep-by-step explanation:
Unclear part of the questionI(t) = −35t² + 800t − 1,000 thousand barrels per day (9 ≤ t ≤ 13) According to the model, approximately when were oil imports to the country greatest? t = ? SolutionGiven the quadratic function
The vertex of a quadratic function is found by a formula: x = -b/2aAs per given function:
b = 800, a = -35Then
t = - 800/2*(-35) = 11.43 which is within given range of 9 ≤ t ≤ 13This time is approximately mid 2012.
Considering this in the function, to get oil import rate for the same time:
l(11.43) = -35*(11.43)² + 800*11.43 - 1000 = 3571.4285Rounded to two significant figures, the greatest oil import rate was:
3600 barrelswhich sign makes the statement true?
Answer:
Less than sign
Step-by-step explanation:
3/4 is greater than 3/5 because its 3 out of 4 making it 75% and 3/5 is 60%
In the diagram of circle A, what is the measure of
ZXYZ?
35°
70°
75°
140°
Using the intersecting secant theorem:
Angle xyz = 1/2( wz- XX)
Xyz = 1/2(175-105)
Xyz = 1/2(70)
Xyz= 35
The answer is 35 degrees
The measure of <XYZ is 35 degrees
Circle geometryTo find the measure of<XYZ, we will use the expression as shown below:
The angle at the vertex is half the difference of the intercepted arcs
<XYZ = 1/2(175 - 105)
<XYZ = 1/2(70)
<XYZ = 35 degrees
Hence the measure of <XYZ is 35 degrees
Learn more on geometry here: https://brainly.com/question/24375372
118 meters in 2 seconds, how many meters in 11 seconds?
Answer:
It would be 649
Step-by-step explanation:
118 ÷ 2= 59
59 x 11= 649
Answer:
649m
Step-by-step explanation:
[tex]\frac{118m}{2s} =\frac{59m}{s}[/tex]
so that 59m/s we multiply by 11s
[tex]\frac{59m}{s} (11s)=649m[/tex]
4 5 6 7 8 9 10 TIME REMAINING 35:22 Triangle KNM is shown. Triangle K N M is shown. Angle M K N is 25 degrees. Angle K N M is 130 degrees. Angle N M K is 25 degrees. What is true about the sides of KNM? KN = NM KN + NM = KM KM = 2(NM) KN = One-halfKM Mark this and return
Answer:
KN = NM
Step-by-step explanation:
Given that:
In a triangle KNM
angle ∠ MKN = 25°
angle ∠ KNM = 130°
angle ∠ NMK = 25°
The objective is to determine what is true about the side of KNM.
The correct option is:
KN = NM
From the above, we will see that two angles are equal, which implies the triangle is likely to be an isosceles triangle. An isosceles triangle is a triangle that has two equal angles and sides.
Thus, the intersection of NK with KM is at an angle of 25°, so do NM and KM. We can thereby conclude that the two sides are equal in length provided that they possess the same angles and they intersect at the line at the same angle.
Answer: (A)
Step-by-step explanation: trust me!
5.1436 rounded to the nearest tenth
Answer:
5.1
Step-by-step explanation:
we have
5.1436
since 4 is less than five we cannot pass the 1 to 2
so it stays like
5.1
Can someone do this for me? I will give brainliest!
Answer:look it up on quizlet
Step-by-step explanation:
A store offers customers a 40% discount on the price of x of selected items. Then, the store takes off an additional 16% at the cash register. Write a price function P(x) that computes the final price of the item in terms of the original price x.
P(x) = ?
Answer:
x-40%-16%
Step-by-step explanation:
what is the simplified expression for -2a^2b+a^2-5ab+3ab^2-b^2+2(a^2b+2ab)
Answer:
Step-by-step explanation:
Hello,
[tex]-2a^2b+a^2-5ab+3ab^2-b^2+2(a^2b+2ab)\\\\=-2a^2b+a^2-5ab+3ab^2-b^2+2a^2b+4ab\\\\=a^2+3ab^2-ab-b^2[/tex]
Thanks
Point G ia on line segment FH Given FG = 5x + 2 GH = 3x -1 and FH = 9 determine the numerical length of FG
Answer:
Step-by-step explanation:
FG=7
For which values of a the system has no solution: x≤5, x≥a
Given:
The system of inequalities is
[tex]x\leq 5[/tex]
[tex]x\geq a[/tex]
To find:
The values of a for which the system has no solution.
Solution:
We have,
[tex]x\leq 5[/tex] ...(1)
It means the value of x is less than or equal to 5.
[tex]x\geq a[/tex] ...(2)
It means the value of x is greater than or equal to a
Using (1) and (2), we get
[tex]a\leq x\leq 5[/tex]
But if a is great than 5, then there is no value of which satisfies this inequality.
Therefore, the system has no solution for a>5.
I really need help with this question
Answer: my sis helped me a little so i think its right try 1,500
Step-by-step explanation:
if she gets paid 849000 a year then i would divide 849000 by 12 cause theres that meany months in a year then with that number subtract the Christmas plus witch is 5500 and thats the answer i think
Find the first partial derivatives of the function f(x,y,z)=4xsin(y−z)
Answer:
[tex]f_x(x,y,z)=4\sin (y-z)[/tex]
[tex]f_x(x,y,z)=4x\cos (y-z)[/tex]
[tex]f_z(x,y,z)=-4x\cos (y-z)[/tex]
Step-by-step explanation:
The given function is
[tex]f(x,y,z)=4x\sin (y-z)[/tex]
We need to find first partial derivatives of the function.
Differentiate partially w.r.t. x and y, z are constants.
[tex]f_x(x,y,z)=4(1)\sin (y-z)[/tex]
[tex]f_x(x,y,z)=4\sin (y-z)[/tex]
Differentiate partially w.r.t. y and x, z are constants.
[tex]f_y(x,y,z)=4x\cos (y-z)\dfrac{\partial}{\partial y}(y-z)[/tex]
[tex]f_y(x,y,z)=4x\cos (y-z)[/tex]
Differentiate partially w.r.t. z and x, y are constants.
[tex]f_z(x,y,z)=4x\cos (y-z)\dfrac{\partial}{\partial z}(y-z)[/tex]
[tex]f_z(x,y,z)=4x\cos (y-z)(-1)[/tex]
[tex]f_z(x,y,z)=-4x\cos (y-z)[/tex]
Therefore, the first partial derivatives of the function are [tex]f_x(x,y,z)=4\sin (y-z), f_x(x,y,z)=4x\cos (y-z)\text{ and }f_z(x,y,z)=-4x\cos (y-z)[/tex].
enter an inequality that represents the graph
PLEASE HELP QILL GIVE BRAINLIEST