Answer:
Step-by-step explanation:
Given that:
The population mean μ = 900
The sample size n = 53
The sample mean = 841
The standard deviation = 190
The level of significance = 0.01
To test the claim that the mean balance of the accounts has decreased during the period.
The null and the alternative hypothesis can be computed as:
[tex]H_o : \mu \ge 900 \\ \\ H_1 : \mu < 900[/tex]
This is a left-tailed test since the alternative is less than 900
The test statistics can be computed as:
[tex]Z = \dfrac{\overline x - \mu}{\dfrac{s}{\sqrt{n}} }[/tex]
[tex]Z = \dfrac{841 -900}{\dfrac{190}{\sqrt{53}} }[/tex]
[tex]Z = \dfrac{-59}{\dfrac{190}{7.28}}[/tex]
Z = -2.26
The p-value = P(Z < -2.26)
From the z-tables
The p-value = 0.01191
The p-value ≅ 0.012
Decision rule: To reject the null hypothesis if the significance level is > p-value.
We failed to reject the null hypothesis.
Conclusion: Thus, there is insufficient evidence to conclude that such accounts mean balance has decreased during this period.
If f(x) = 2/3x - 6, find f^-1. Justify your answer using the composition of functions f(f^-1(x))=f^-1(f(x))
Answer:
[tex]f^{-1}(x)= \frac{3}{2}(x+6)[/tex]
[tex]f(f^{-1}(x)) = f^{-1}(f(x))= x[/tex]
Step-by-step explanation:
Given
[tex]f(x) = \frac{2}{3}x - 6[/tex]
Required
Determine [tex]f^{-1}(x)[/tex]
[tex]f(x) = \frac{2}{3}x - 6[/tex]
Represent f(x) as y
[tex]y=\frac{2}{3}x - 6[/tex]
Swap the positions of x and y
[tex]x=\frac{2}{3}y - 6[/tex]
Add 6 to both sides
[tex]x+6=\frac{2}{3}y - 6+6[/tex]
[tex]x+6=\frac{2}{3}y[/tex]
Multiply both sides by 3
[tex]3(x+6)=\frac{2}{3}y * 3[/tex]
[tex]3(x+6)=2y[/tex]
Divide both sides by 2
[tex]\frac{3}{2}(x+6)=\frac{2y}{2}[/tex]
[tex]\frac{3}{2}(x+6)=y[/tex]
[tex]y= \frac{3}{2}(x+6)[/tex]
Replace y with [tex]f^{-1}(x)[/tex]
[tex]f^{-1}(x)= \frac{3}{2}(x+6)[/tex]
Justify the result:
First, we solve for [tex]f(f^{-1}(x))[/tex]
[tex]f(x) = \frac{2}{3}x - 6[/tex]
[tex]f(x) = \frac{2}{3}x - 6[/tex] becomes
[tex]f(f^{-1}(x)) = \frac{2}{3}x - 6[/tex]
Substitute [tex]\frac{3}{2}(x + 6)[/tex] for x
[tex]f(f^{-1}(x)) = \frac{2}{3}(\frac{3}{2}(x + 6)) - 6[/tex]
[tex]f(f^{-1}(x)) = \frac{2*3}{3*2}(x + 6)- 6[/tex]
[tex]f(f^{-1}(x)) = \frac{6}{6}(x + 6)- 6[/tex]
[tex]f(f^{-1}(x)) = 1*(x + 6)- 6[/tex]
[tex]f(f^{-1}(x)) = x + 6- 6[/tex]
[tex]f(f^{-1}(x)) = x[/tex]
Next, we solve [tex]f^{-1}(f(x))[/tex]
[tex]f^{-1}(x)= \frac{3}{2}(x+6)[/tex]
[tex]f^{-1}(x)= \frac{3}{2}(x+6)[/tex] becomes
[tex]f^{-1}(f(x))= \frac{3}{2}(x+6)[/tex]
Substitute [tex]\frac{2}{3}x - 6[/tex] for x
[tex]f^{-1}(f(x))= \frac{3}{2}(\frac{2}{3}x) - 6+6[/tex]
[tex]f^{-1}(f(x))= \frac{3}{2}(\frac{2}{3}x)[/tex]
[tex]f^{-1}(f(x))= \frac{2*3}{3*2}x[/tex]
[tex]f^{-1}(f(x))= \frac{6}{6}x[/tex]
[tex]f^{-1}(f(x))= 1*x[/tex]
[tex]f^{-1}(f(x))= x[/tex]
Hence:
[tex]f(f^{-1}(x)) = f^{-1}(f(x))= x[/tex]
A right triangle has a base equal to 13 inches and a height equal to 18 inches. Find the area of the trlangle.
Answer:
117
Step-by-step explanation:
The formula for a triangle is base times hight divided by two. So, 13 x 18 = 234, and 234/2 = 117
Riley wants to make 100 ml of 25% saline solution but only has access to 12% and 38% saline mixtures.
To make 100 ml of 25% saline solution, Riley will need 50 ml = 12% saline mixture and 50 ml= 38% saline mixture.
Given,
We have 12% and 38% of saline mixtures.
We need to find the amount in ml from each saline mixture which would give us 100 ml of 25%.
What are the methods to solve a system of linear equations?
There are a number of methods but the most and easiest used method is the substitution method and the elimination method.
We can make two linear equations from the given statements.
Let x = amount from 12% saline mixture and y = amount from 38% saline mixture.
Now we need to make 100 ml of 25% saline.
so,
x + y = 100.
So we have two equations.
x + y = 100..............(1)
12% of x + 38% of y = 100 x 25%
0.12x + 0.38 = 25 ...............(2)
Using the substitution method we have,
x = 100 - y
Putting x = 100 - y in {2}
0.12 ( 100 - y ) + 0.38y
= 2512 - 0.12y + 0.38y
= 250.38y - 0.12y
= 25 - 120.26y = 13y
= 13 / 0.26y = 50.
Putting y = 50 in (1)
x + y = 100x
100 -50x = 50.
So Riley will need 50 ml = 12% saline mixture and 50ml = 38% saline mixture to make 100 ml of 25% saline solution.
Learn more about finding proportion of mixtures here:
https://brainly.com/question/20366557
#SPJ2
Jin can purchase 10 gallons of biodegradable fuel for $42.99 at the local
gas station. Which of the following deals costs less per gallon? *
O 8 gallons of fuel for $38.50
O 15 gallons of fuel for $60.50
0 20 gallons of fuel for $91.75
30 gallons of fuel for $131.40
Answer:
b 15 gallons of fuel for $60.50
Step-by-step explanation:
because 1 gallon of fuel is for $4.299
and when you multiply 15×4.299 the answer is 64.485 which is greater than the offer you are getting it for.
Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the height of a man with a z-score of 0.2 (to 2 decimal places)
Answer:
69.04
Step-by-step explanation:
Given that:
Mean (m) = 69.0
Standard deviation (s) = 2.8
Zscore = 0.2
Find the corresponding height (x) ;
Using the relation :
Zscore = (x - m) / s
0.2 = (x - 69.0) / 0.2
0.04 = x - 69.0
0.04 + 69.0 = x
69.04 = x
Hence, the height of a man with a Zscore of 0.2 is 69.04
1. Jessica starts at an elevation of 40 feet and descends 60 feet. Use the
number line to find Jessica's current elevation. Then complete the equation.
-80-70-60-50-40-30-20-10 0 10 20 30 40 50 60 70 80 90 100 110 120
---
40 + (-60) =
Answer:
Jessicas current elevation is -20 feet.
Step-by-step explanation:
Start and 40 on the number line and make a straight line to -20 on the number line with dots at 40 and -20 on the number line
What is the outlier in this data set 23,31,28,73,19
Owen earns $27,980 per year in take-home pay. What is the most money a
housing expert would advise him to spend on a monthly mortgage payment?
O A. $2798.00
B. $582.92
C. $279.80
O D. $466.33
Two lemon creams plus four fudge cookies have 450 calories. Four lemon creams plus two fudge cookies have 420 calories. How many calories are in each cookie?
Answer:
Each fudge cookie has 80 calories.
Each lemon cream has 65 calories.
Step-by-step explanation:
We will let [tex]\ell[/tex] represent the calories in lemon creams and [tex]f[/tex] represent the calories in fudge cookies.
Two lemon creams and four fudge cookies together have 450 calories. So, we can write the following equation:
[tex]2\ell+4f=450[/tex]
And four lemon creams plus two fudge cookies together have 420 calories. So, we can write the following equation:
[tex]4\ell+2f=420[/tex]
We now have a system of equations. We can solve this by elimination.
For the first equation, we can multiply both sides by -2. This way, the [tex]\ell[/tex] will cancel when we add the two equations together.
So, the first equation becomes:
[tex]-4\ell-8f=-900[/tex]
Add this to the second equation. Hence:
[tex](-4\ell+4\ell)+(-8f+2f)=(-900+420)[/tex]
Simplify:
[tex]-6f=-480[/tex]
Divide both sides by -6. Hence:
[tex]f=80[/tex]
So, there are 80 calories in one cookie.
We can use the first equation again to find the amount of calories in one cream. We have:
[tex]2\ell+4f=450[/tex]
Substituting 80 for [tex]f[/tex] yields:
[tex]2\ell+320=450[/tex]
Then it follows that:
[tex]\ell=65[/tex]
So, there are 65 calories in each lemon cream.
Answer:
567
Step-by-step explanation:
We are told that the two players, taken together, scored a total of 49 points. What is the probability that player A scored first?
Answer:
1/2 or 50% probability
Step-by-step explanation:
There are just two players, player A and player B. Since it is between this two players, for player A to score first we would have:
AB where player A is the first player to score, we wouldn't have BA since player would not be the first here
Probability = number of favorable outcomes/total number of outcomes
Therefore probability of A being the first player = number of A/total number of players
=1/2 = 0.50
There is therefore a 50% chance of A being the first player
please help!!!! find x and y
9514 1404 393
Answer:
(x, y) = (10, 2)
Step-by-step explanation:
The upper angle marked with an expression in x and y is supplementary to the angle marked 70°. The lower angle marked with an expression in x and y is an alternate interior angle with respect to the one marked 70°, is equal to that. This gives the two equations in x and y:
6x +10y +30 = 110
4x +10y +10 = 70
Subtracting the second equation from the first gives ...
2x +20 = 40
x +10 = 20 . . . . . divide by 2
x = 10 . . . . . . . . . subtract 10
Substituting into the second equation gives ...
4(10) +10y +10 = 70
4 + y + 1 = 7 . . . . . . . . divide by 10
y = 2 . . . . . . . . . . . . . . subtract 5
The values of x and y are 10 and 2, respectively.
Answer:
9514 1404 393
Step-by-step explanation:
Describe another pattern you see in this set of numbers 20,24,28,32, and 36
Which expression represents
"thirty-eight less than the sum of forty and nineteen"?
A 38 – 40 + 19
® 38 - (40 – 19)
19+ (40 – 38)
D (40+ 19) – 38
Answer:
(40+ 19) – 38
Step-by-step explanation:
We need to find the expression for "thirty-eight less than the sum of forty and nineteen".
Sum of forty and nineteen = 40 + 19
38 less than the above is 40 + 19 - 38
Overall expression is :
(40 + 19) - 38
Hence, the correct option is (d) "(40+ 19) – 38".
Multiply. Write your answer as a fraction in simplest form.
Answer: 9/11
Step-by-step explanation:
Answer:
9/11
Step-by-step explanation:
3/22 * 6/1= 18/22
18/22 divided by 2 = 9/11
DUE AT 11:59 PLEASE ANSWER NOW
Answer:
g = 6
Step-by-step explanation:
5.2g + 10 = 2.2g + 28 (Given)
3g + 10 = 28 (Subtracted 2.2g on both sides)
3g = 18 (Subtracted 10 on both sides)
g = 6 (Divided 3 on both sides)
To check to make sure you are correct, simply substitute your answer for g:
5.2(6) + 10 = 2.2(6) + 28
31.2 + 10 = 13.2 + 28
41.2 = 41.2
You'll know you're correct if they both equal the same. In this case, the solution works.
ngl i kinda wanna boo anyone down :)
Answer:yo it’s me leo remember me my acount got deleted
Step-by-step explanation:
Find the number if 12/13 of it is 24 plz help
Step-by-step explanation:
12/13 of a number = 24
13/13 of a number = 24 * (13/12) = 26
Hence the number is 26.
Answer:
26
Step-by-step explanation:
Let n be the number. Then:
12n/13=24
n=13/12 x 24
=26 ..............
En un Gran Premio de Fórmula 1, diez pilotos han obtenido estos tiempos en la clasificación. ¿Cuál es el orden de salida?
Answer:
WHat did he say
Step-by-step explanation:
Imani is training for a half marathon. The graph shows her distance during a 60-minute practice run.
PLEASE ANSWER THIS QUESTION RIGHT THE QUESTION IS ABOVE THE PICTURE
Answer: its C
Step-by-step explanation: Ive taken this question dont know how but its C.
The drama club is selling short-sleeved shirts for $5 Let x represent the number of short-sleeved shirts
each, and long-sleeved shirts for $10 each. They hope to ordered and let y represent the number of long-sleeve
sell all of the shirts they ordered, to earn a total of
shirts ordered.
$1,750. After the first week of the fundraiser, they sold How many short-sleeved shirts were ordered?
3
of the short-sleeved shirts and 15 of the long-sleeved
How many long-sleeved shirts were ordered?
shirts, for a total of 100 shirts.
This system of equations models the situation.
5x + 10y = 1,750
**+ y = 100
This data is Inaccurate Data
Equations of the system are When The situation is described is modeled by the following system of equations: Step first 5x + 10y = 1,750 Step second x + y = 100Where are
x = number of short-sleeved shirts y = number of long-sleeved shirtsDivide first by 5:
Then third step will be x + 2y = 350Multiplye secondly by -2:
-2x - 2y = -200
Add with the third one -x = 150 x = -150 Then, The value of x should not be negative. also, This happens because the problem is inaccurately stated. Not even selling 100 of the $10 shirts we can get to $1,750. If the total shirts sold was 200, then it secondly x + y = 200 And then x = 50, y=150 was an acceptable solution.Learn more:
https://brainly.com/question/12010307
Please help I will give brainliest only to those who answer respectfully and the best answer
I need a topic on standard deviation, I'm supposed to be teaching first graders how to do standard deviation I just dont have a topic that would relate to them, could you please give me one?
Answer:
possibly you could use kid per candy, number of trickery treaters or something
you could explain lets say over the holidays Miss. So and So's class's kids got an average of around 4-6 Christmas presents while Miss. Mary Sue's class had kids with 2 presents and kids with 12, since the range between 2-12 is bigger it had a greater standard of deviation
(hopefully this helps and I am not overcomplicating or incorrecting the standard of deviation, good luck)
Given m||n, find the value of x.
+
(8x-4)º
(6x-12)
Answer:
x = 14
Step-by-step explanation:
(6x - 12)° + (8x - 4)° = 180° (Supplementary angles)
6x - 12 + 8x - 4 = 180
Add like terms
14x - 16 = 180
14x = 180 + 16
14x = 196
x = 196/14
x = 14
Please help, and explain step by step, thanks!
Both attachments are part of the same problem
Answer:
Answer: B San Francisco
Step-by-step explanation:
It can be read that Geneva is 12°C colder than Nikki's hometown. It can be seen in the table that Geneva is at -3°C.
This means that Nikki's hometown is 12°C hotter than Geneva, thus:
Temperature of Nikki's hometown = -3°C + 12°C = 9°C.
The only city with a temperature of 9°C is San Francisco.
Answer: B San Francisco
The table shows the price for different numbers of board games:
Number of Board Games Price (in dollars)
2 7
4 14
5 17.50
9 31.50
Does this table of numbers represent a proportional relationship? (5 points)
a
Yes, because 3.5 times the price is the number of board games
b
Yes, because the price is 3.5 times the number of board games
c
No, because the price of 4 board games should be $9 and not $14
d
No, because the price of 9 board games should be $40.50 and not $31.50
Answer:
We conclude that the price is 3.5 times the number of board games.
Hence, option B is true.
Step-by-step explanation:
We know that when y varies directly with x, the equation is
y ∝ x
y = kx
k = y/x
where 'k' is called the proportionality constant.
From the table,
For the point (2, 7)
k = y/x
= 7/2
= 3.5
For the point (4, 14)
k = y/x
= 14 / 4
= 7/2
= 3.5
For the point (5, 17.50)
k = y/x
= 17.5 / 5
= 3.5
For the point (9, 31.50)
k = y/x
= 31.50 / 9
= 3.5
From the above calculations, we computed that the value of the proportionality constant remains the same.
Thus, the table of numbers represents a proportional relationship.
Therefore, the equation becomes
y = kx
The price of 2 board game
y = 3.5 (2)
= 7
The price of 4 board game
y = 3.5 (4)
= 14
Therefore, we conclude that the price is 3.5 times the number of board games.
Hence, option B is true.
how do you find the area of this problem
Answer: 240
Step-by-step explanation:
You would multiply each of the sides to get the final answer of 240 (:
I need help finding the m
if you roll a standard 6 sided die, whats the probability that you get a 1,2,3,5, or 6?
Answer:
5/6
Step-by-step explanation:
1 has a 1/6 chance2 has a 1/6 chance3 has a 1/6 chance5 has a 1/6 chance6 has a 1/6 chance1, 2, 3, 5, or 6 has a 1/6+1/6+1/6+1/6+1/6=5/6 chanceAnswer:
18.3% chance it will land on that particular side
What is m<9?
Your response should be at least 3 complete sentences. Be sure to include any relevant measurements and calculations. FAILURE TO SHOW WORK WILL RESULT IN A LOSS OF POINTS. no plagiarism!!
9514 1404 393
Answer:
70°
Step-by-step explanation:
Angles 2 and 13 are alternate exterior angles, so are congruent. The value of x can be found by solving the equation that equates the expressions for the measures of these angles. Once x is found, the measure of angle 13 can be determined. The measure of angle 9 is the supplement of angle 13.
So, ...
m∠2 = m∠13
8x +14 = 10x -10
24 = 2x . . . . . . . . add 10-2x
12 = x
m∠13 = 10x -10 = 10·12 -10 = 110
m∠9 = 180° -110°
m∠9 = 70°
5 The temperature on Janice's birthday is -10.6°C. Which absolute value equation BEST describes how many degrees below 0°C the temperature is on Janice's birthday?
A) l–10.6l = 10
B) l–10.6l = –10.6
C) l–10.6l = –10
D) l-10.6l = 10.6