Answer:
a)= 2
b) 6.324
c) P= 0.1217
Step-by-step explanation:
a) The mean of the sampling distribution of X`1- X`2 denoted by ux`-x` = u1-u2 is equal to the difference between population means i.e = 2 ( given in the question)
b) The standard deviation of the sampling distribution of X`1- X`2 ( standard error of X`1- X`2) denoted by σ_X`1- X`2 is given by
σ_X`1- X`2 = √σ²/n1 +σ²/n2
Var ( X`1- X`2) = Var X`1 + Var X`2 = σ²/n1 +σ²/n2
so
σ_X`1- X`2 =√20 +20 = 6.324
if the populations are normal the sampling distribution X`1- X`2 , regardless of sample sizes , will be normal with mean u1-u2 and variance σ²/n1 +σ²/n2.
Where as Z is normally distributed with mean zero and unit variance.
If we take X`1- X`2= 0 and u1-u2= 2 and standard deviation of the sampling distribution = 6.324 then
Z= 0-2/ 6.342= -0.31625
P(-0.31625<z<0)= 0.1217
The probability would be 0.1217
A researcher wants to estimate the mean commute time of residents in Westchester County. The researcher samples 40 commuters and find the mean commute time to be 25 minutes. Assume the population standard deviation for commute time is 12.5 minutes. Construct a 90% confidence interval for the mean commute time of residents in Westchester County. What is the Lower Bound of the confidence interval
Answer:
21.759
Step-by-step explanation:
Given that :
Mean (m) = 25
Standard deviation (s) = 12.5
Sample size (n) = 40
α = 90%
The confidence interval is obtained using the relation:
Mean ± Zcritical * s/sqrt(n)
Zcritical at 90% confidence interval = 1.64
25 ± 1.64 * (12.5/sqrt(40))
Lower boundary : 25 - 1.64(1.9764235) = 21.75866546
Upper boundary : 25 + 1.64(1.9764235) = 28.24133454
(21.759, 28.241)
Hence, lower bound of confidence interval is : 21.759
I need help finding an eqaution for this. Thank you in advanced
Answer:
Formula: [tex]c=\frac{sale\ price\ of\ 7}{7}+\$0.75[/tex]
Normal Price: [tex]\$1.15[/tex]
Step-by-step explanation:
First, you have to find the current price of one cookie.
Since 7 cookies cost $2.80, then the price for one sale price cookie would cost
Then you would have to add the $0.75 to the sale price to get the normal price.
[tex]\$0.4\ +\ \$0.75=\$1.15[/tex]
The normal price of a cookie would be $1.15.
The formula to get that answer would be:
[tex]c=\frac{sale\ price\ of\ 7}{7}+\$0.75[/tex]
Hope this helps!
Drag the phrases into the box to match each expression. 4x – 5 4 (x – 5) 4 ( x + 5) 5 less than the sum of 4 and a number 5 less than the product of 4 and a number the product of 4 and the difference of a number and 5 4 more than the sum of a number and 5 5 more than the product of 4 and a number the product of 4 and the sum of a number and 5 4 more than 5 less than a number
Answer:
4x – 5
4 (x – 5)
4 ( x + 5)
5 less than the sum of 4 and a number
5 less than the product of 4 and a number
the product of 4 and the difference of a number and 5
4 more than the sum of a number and 5
5 more than the product of 4 and a number
the product of 4 and the sum of a number and 5
4 more than 5 less than a number
[tex] \frac{18}{100} [/tex]
is what percent
A. 36%
B. 8%
C. 9:
D. 18%
To walk to her friend's house, Cristal normally walks 63 yards north and 16 yards east as shown. How many
yards shorter would it be if Julie took the diagonal shortcut, x?
16 yd
63 yd
х
A
(10
Answer:
65 yd
Step-by-step explanation:
The image of this walking path of Cristal is missing, so i have attached it.
From the image attached, we can see that the path "x" is the hypotenuse path a the triangle.
Thus, we can use pythagoras theorem to find the area. Thus;
x² = 16² + 63²
x = √(16² + 63²)
x = √4225
x = 65 yd
Evaluate (1 2/3)^3. A. 3 8/27 B. 4 8/27 C. 4 4/9 D. 4 17/27
Answer:
D. 4 17/27
Step-by-step explanation:
(1 2/3)^3 = (1 + 2/3)^3 = (3/3 + 2/3)^3 = (5/3)^3 = (5 * 5 * 5)/(3 * 3 * 3) = 125/27 = 108/27 + 17/27 = 4 17/27
Answer:
D
Step-by-step explanation:
[tex](1\frac{2}{3})^3\\\\(1+\frac{2}{3})^3\\\\(\frac{3}{3}+\frac{2}{3})^3\\\\(\frac{5}{3})^3\\\\\frac{5^3}{3^3}\\\\\frac{125}{27}\\\\\frac{(27*4)+17}{27}\\\\4\frac{17}{27}[/tex]
Please help me fast!!!. Joe and his family are touring Chicago. They want to visit the Willis Tower, hang out at Navy Pier, and shop on Michigan Avenue before their dinner reservations at 5:10 P.M. They plan to spend 1 hour and 10 minutes at the Willis Tower, 3 hours and 10 minutes at Navy Pier, and 1 hour and 15 minutes shopping. What is the latest time Joe's family can start their tour of Chicago and still make it to dinner on time?
Include A.M. or P.M. in your answer.
Answer:
11:10 am.
Step-by-step explanation:
The first thing I'm going to do is to add all the given time together
Total time = time spent at Willis tower + time spent at Navy Pier + time spent shopping
Total time = 1 HR and 10 minutes + 3 HR and 10 minutes + 1 hour and 15 minutes
Total time = (1 + 3 + 1) hr + (10 + 10 + 15) minutes
Total time = 5 hours + 35 minutes
The question doesn't make mention of how long they spent making the journey so, I'm assuming they spent 35 minutes driving around from Willis to the Pier and finally while shopping
Time = total time + time spent driving
Time = 5 hours 35 minutes + 35 minutes
Time = 6 hours and 10 minutes
Now, this time we've calculated, is what we're going to subtract from the dinner time to get our final answer
Needed time = dinner time - time
Needed time = 5:10 pm - 6:10
Needed time = 17:10 - 6:10
Needed time = 11:10
This means that they ought to start their tour by 11:10 am, so that they can meet their dinner
An 8-foot rope is tied from the top of a pole to a stake in the ground,as shown in the diagram below.
If the rope a 57° angle with the ground, what is the height of the pole, to the nearest tenth of a foot?
A 4.4
B 6.7
C 9.5
D 12.3
The height of the pole, to the nearest tenth of a foot is given by: Option B: 6.7 feet
What is angle of elevation?You look straight parallel to ground. But when you have to watch something high, then you take your sight up by moving your head up. The angle from horizontal to the point where you stopped your head is called angle of elevation.
How to use right triangles to find the height of the specified pole?Remember that we assume that pole is vertical to the ground. This means, there is 90° formation. The length of the rope can be taken as length of hypotenuse.
Referring to the attached figure below, we get:
Length of the rope = length of AC = |AC| = 8 feetThe angle of elevation of rope from ground: 57°Using the tangent ratio, we get:
[tex]\sin(x) = \dfrac{\text{Length of perpendicular}}{\text{Length of hypotenuse}} = \dfrac{|AB|}{|AC|}\\\\|AB| = \sin(x) \times |AC|\\\\|AB| = \sin(57^\circ) \times 8 \approx 6.71 \approx 6.7\: \rm feet[/tex]
Thus, the length of the pole is approx 6.7 feet (option B).
Learn more about trigonometric ratios here:
https://brainly.com/question/22599614
1) James needs to obtain $80,000 for his daughter's future college tuition. He is looking to invest in an
account that pays 3.1% annual interest. The account compounds quarterly. How much money would
James have to invest today so that 15 years from now, he will have the money?
Answer:
$ 50,340.97
Step-by-step explanation:
From the above question, we can deduce that we are to find the Initial amount invested which is also called the Principal.
The formula to find Principal in a compound interest question is:
P = A / (1 + r/n)^nt
Where:
A = Total Amount obtained after invested = $80,000
r = Interest rate = 3.1% = 0.031
n = number of times interest in compounded = Quarterly = 4
t = time in years = 15
P = $80,000/(1 + 0.031/4)^4 × 15
P = $80,000/(1 +0.00775)^60
P = $ 50,340.97
Hence, James would have to invest $50,340.97 today to have $80,000 in 15 years.
need help plz thanks
Answer:
its B
Step-by-step explanation:
Answer:
5x+6=10+10=8x-15
Step-by-step explanation:
An airport limo service charges riders a fixed charge of $15 plus
$4.00 per mile. How many miles must a rider go to have an
average cost per mile of $4.60?
Given:
An airport limo service charges riders a fixed charge of $15 plus $4.00 per mile.
To find:
Distance in miles must a rider go to have an average cost per mile of $4.60.
Solution:
Let x be the number of miles the rider travel.
Total charges = Fixed charges + Variable charges
According to the question,
Fixed charges = $15
Variable charges = $4x
So, total charges
[tex]T=15+4x[/tex]
Divide the total charges by number of miles to get the cost per mile.
[tex]\text{Cost per mile}=\dfrac{15+4x}{x}[/tex]
Average cost per mile is $4.60.
[tex]4.60=\dfrac{15+4x}{x}[/tex]
[tex]4.60x=15+4x[/tex]
[tex]4.60x-4x=15[/tex]
[tex]0.60x=15[/tex]
Divide both sides by 0.60.
[tex]x=\dfrac{15}{0.60}[/tex]
[tex]x=25[/tex]
Therefore, the required number of miles is 25.
Select all possible values for x if −3x < 15.
Select one or more:
A. -11
B. -7
C. -5
D. 2
E. 9
Step-by-step explanation:
When dividing or multiplying by a negative number, remember to flip the inequality sign.
-3x < 15
x > -5 (divide -3 on both sides, flip the inequality sign)
The correct options are 2 and 9. (D and E)
Answer:
D. 2
E. 9
Step-by-step explanation:
[tex] - 3x < 15 \\ \\ x > \frac{15}{ - 3} \\ \\ x > - 5 \\ \\ [/tex]
Since x > - 5,
Therefore possible values of x would be 2 and 9 out of the given ones.
Branson purchased a wooden board 9/10 yard long to split into smaller pieces for a project. If he cuts them into smaller pieces that are each 1/12 yard long. How many boards will we have?
Answer:YASSA POINTS
Step-by-step explanation:
100
3
80
6
60
9
40
20
0
100
web and Windows
BE
a
02 AM
NETT Dann
Answer:
Uhhhh what?
Step-by-step explanation:
I am confused...
PLEASE HELP!!!!!!!!!!!!!!
PLEASE HELP ME!!
40 Points!!
Select all factors of the following polynomial:
4p3 + 36p² + 32p
Select all that apply
• 4p
• 4p^2
• (p-1)
• (p+1)
• (p-2)
• (p+2)
• (p-4)
• (p+4)
• (p-8)
• (p+8)
40+32=72
THE RESON IT IS SEVENTYTWO IS BECAUSE IT IS 72p^2
Factors of the given polynomial are 4p, (p + 1) and (p + 8).
Given polynomial in the question,
4p³ + 36p² + 32pFactorize the polynomial,
4p³ + 36p² + 32p = 4p(p² + 9p + 8)
= 4p(p² + 8p + p + 8)
= 4p[p(p + 8) + 1(p + 8)]
= 4p(p + 1)(p + 8)
Therefore, 4p, (p + 1) and (p + 8) are the factors of the given polynomial.
Learn more,
https://brainly.com/question/15156417
Can someone help me out.
Answer:
63 sq
Step-by-step explanation:
9*7
Tommy is using a bucket to collect nuts from a nut tree. He then dumps the bucket into a barrel for shipping of the nuts. He notices that 1 over 4 bucket of nuts fills 2 over 3 of the barrel.
Part A: Write and solve an equation to find the amount of nuts that will fill the entire barrel. Show your work. (8 points)
Part B: Explain your answer in words. (2 points)
Your answer:
Answer: you need 3/8 buckets of nuts to fill the barrel.
Step-by-step explanation:
I will find the equation and explain it with words at the same time, so it is easier to understand.
We know that:
1/4 buckets of nuts, fills 2/3 of the barrel.
Then we can write the equation:
(1/4) buckets of nuts = (2/3) of the barrel
We want to have a one in the right, which will mean that the barrel is complete, then we can multiply both sides by 3/2
(3/2)*(1/4) buckets of nuts = (3/2)*(2/3) of the barrel.
3/8 buckets of nuts = 1 of the barrel.
This means that you need 3/8 buckets of nuts to fill the barrel.
Decide whether the normal sampling distribution can be used. If it can be used, test the claim about the population proportion p at the given level of significance alpha using the given sample statistics. Claim: p is not equal to 0.22; Alpha = 0.01; Sample statistics: p = 0.15, n = 180Can the normal sampling distribution be used? A. No, because np is less than 5. B. No, because nq is less than 5. C. Yes, because both np and nq are greater than or equal to 5. D. Yes, because pq is greater than alpha = 0.01. State the null and alternative hypotheses. Determine the critical value(s).Find the z-test statistic.
Answer:
A
The correct option is C
B
The value of z-test is [tex]z = -2.267[/tex]
Step-by-step explanation:
From the question we are told that
The null hypothesis [tex]H_o : p = 0.22[/tex]
The alternative hypothesis [tex]H_a : p \ne 0.22[/tex]
The level of significance is [tex]\alpha = 0.01[/tex]
The sample proportion is [tex]\^ p = 0.15[/tex]
The sample size is n = 180
Generally from central limit theorem
if np and nq are > 5 then normal sampling distribution can be used
So
np = 180 * 0.22 = 39.6 > 5
and
nq = 180 * (1 -0.22) = 140.4 > 5
So normal sampling distribution can be used
Generally the z-test is mathematically represented as
[tex]z = \frac{\^ p - p }{ \sqrt{\frac{ p(1- p ) }{n } } }[/tex]
=> [tex]z = \frac{ 0.15 - 0.22 }{ \sqrt{\frac{ 0.2(1- 0.22 ) }{ 180 } } }[/tex]
=> [tex]z = -2.267[/tex]
Help?.?.??? I’ll give brainliest to the first person who responses
Answer:
1. y=3x
2. y=1x
3. y=7x
4. y=1x+7
5. y=3x-3
6. y=12x+2
Step-by-step explanation:
Hope this helps!
Which statements describe one of the transformations performed on f(x) =x^2 to create g(x)=2x^2+5?
A: A translation of 5 units to the right
B: A vertical stretch with a scale factor of 1/2
C: A vertical stretch with a scale factor of 2
D: A translation of 5 units up
Answer:
do u know the answer ik it's five units up but that it
Answer: a vertical stretch with a scale factor of 2. and a translation of 5 units up.
Step-by-step explanation:
Can someone help me with these 2 questions real quick?
Answer:
<M = 32 and <Y = 103
Step-by-step explanation:
1. Since triangle BCM is congruent to triangle ZYR, we know the corresponding parts of the triangles are congruent. Therefore, <Z = <B = 45. The sum of a triangle’s angles is 180, so <M = 180 - <B - <C = 180 - 45 - 103 = 32
2. This is the exact same diagram, so we can use the information we have collected in #1. Since corresponding parts of congruent triangles are congruent, <Y must be congruent to <C, which equals 103. Therefore, <Y = 103.
I hope this helps! :)
Suppose you deposit $2,500 in a savings account that pays you 5% interest per year.
a. How many years will it take for you to double your money?
b. How many years will it take for your account to reach $8,000?
Answer:A=4 Years B=6 years
Step-by-step explanation:
Rashad has 24 Almonds and 32 walnuts for making snack bags. he wants to make as many snack bags as possible and wants each bag to have the same amount of almonds and walnuts. What is the largest number of snack bags he could make
A.3 bags
B.4 bags
C. 8 bags
D. 16 bags
what is 48.75% of 204..............
Each bus Ms. Robinson rents can seat 42 children. How many buses does Ms. Robinson need to take 135 students on a field trip?
Answer:mrs robinson would need total of four buses
Step-by-step explanation:
this is because if you have 135 and you divide it by 42 it gets you 3.2 and you cant have .2 of a bus so you must round up to the nearest whole number which would be 4
Help me with this plz!?!? I will mark brainliest!!!
Problem (11), 10 points 3 Math majors and 3 Computer Science majors will be presenting at a conference. Three students will be randomly selected to present on Monday, and the remaining three stu- dents will present on Tuesday.
(a, 3 points) What is the probability that two Computer Science majors and a math major will present on Tuesday? You do not need to simplify your answer.
(b, 5 points) Suppose we know at least one Math major has been selected to present on Monday. What is the probability that two Computer Science majors and a math major will present on Tuesday, given this information?
(c, 2 points) Based on your answer for b, are the events ‘at least one math major is selected to present on Monday' and 'two computer science majors and a math major present on Tuesday' independent?
Answer:
a}[tex]P_1= 0.3[/tex]
b)[tex]P_2 =0.45[/tex]
c) NOT INDEPENDENT
Step-by-step explanation:
From the question we are told that
Sample space
Math majors are 3
computer science majors are 3
Generally the sample space is
Mathematically the sample space required on Monday is given as [tex]S_m= 3c_1 * 3C_2[/tex]
where [tex]S_m[/tex] =sample space on Monday
Therefore,
[tex]P_1[/tex] = [tex]\frac{3C_1 *3C_2}{6C_3}[/tex]
[tex]P_1=\frac{3*3}{20}[/tex]
[tex]P_1=\frac{6}{20}[/tex]
b)
Generally the the equation is given as
[tex]P_2 =P(\frac{x \cap y}{y})[/tex]
where
x is selecting two math major and 1 computer science major on Monday
y is at leas one math major selected
[tex]P_2 =\frac{^3C_1*^3C_2}{^3C_1*^3C_2 + ^3C_2*^3C_1 +^3C_3*^3C_0}[/tex]
[tex]P_2 =\frac{3*3}{3*3 + 3*3 +^1*1}[/tex]
c)
Generally in representing independent events
[tex]P_3=p(x \cap y)[/tex]
=>[tex]p(x) * p(y)[/tex]
Mathematically
[tex]n(x)= ^3C_1 *^3C_2[/tex]
[tex]n(y)={^3C_1*^3C_2 + ^3C_2*^3C_1 +^3C_3*^3C_0}[/tex]
therefore
[tex]n(x \cap y) =^3C_1 *^3C_2[/tex]
This does not satisfy the two equations stated above therefore NOT INDEPENDENT
10. You can model the population of a Florida town between the years 1980 and 2015 by
the function f(x) = 90,000(x – 1960), where x is the year. In what year did the town have a
population of 450,000?
NEED URGENT HELP 50 POINTS MATH EQUATION PLEASE NO POINT STEAL!
Answer:
2 is the number of dollars per seed.
6 is the number of lettuce seeds bought.
7 is the number of pea seeds bought.
Step-by-step explanation:
Two dollars multiplied by six plus seven packets of seeds.