Answer:
a) = x1`-x2`/ Sp √ ( 1/n₁ + 1/n₂)
b) it is assumed that the population standard deviations are known (which is sometimes met and sometimes not known).
c) The Confidence interval = [ 19131.77, 36868.23]
Step-by-step explanation:
Part a:
The 99% confidence interval for the difference between the average salaries of male and female neurologists is given by
(x1`-x2`) ±t∝/2(υ)* √ ( Sp²/n₁ + Sp²/n₂)
= x1`-x2`/ Sp √ ( 1/n₁ + 1/n₂)
where Sp ²= s₁² ( n1-1) + s₂²(n2-1) /(n1-1) + (n2-1)
Part B:
1) the sample should be normally distributed
2) it is assumed that the population standard deviations are known (which is sometimes met and sometimes not known).
Part C:
Calculations
1) H0: μ₁=μ₂ against the claim Ha: μ₁ ≠μ₂
2)The test statistic is
t= x1`-x2`/ √ ( Sp²/n₁ + Sp²/n₂)
where
Sp ²= s₁² ( n1-1) + s₂²(n2-1) /(n1-1) + (n2-1)
= 15,000²(17) + 22,000²(22) / 37
Sp ²= 103378640
3) D.f = n1+n2-2 =21+18-2 = 37
4) for 2 tailed test the critical value of t is obtained by
t≥ t∝/2 ( d.f)=t≥ t0.005 (37)= ±2.7154= ± 2.72
5) Putting the values
(x1`-x2`) ±t∝/2(υ)* √ ( sp²/n₁ + sp²/n₂)
28000 ± (2.72 * 3265.89)
=[ 19131.77, 36868.23].
The Confidence interval = [ 19131.77, 36868.23]
Hei has $1,300 in a retirement account earning 4% interest compounded annually. Each year after the first, she makes additional deposits of $1,300. After 5 years, what was her account balance if she did not make any withdrawals? Round each year's interest to the nearest cent if necessary.
The account had a balance of $
after 5 years.
Answer:
Her account balance after 5 years is $8702.87
Step-by-step explanation:
1500 (1.05) = 1575 --> after one year
1575 + 1500 = 3075
3075 (1.05) = 3228.75 --> after two years
3228.75 + 1500 = 4728.75
4728.75 (1.05) = 4965.1875 --> after three years
4965.1875 + 1500 = 6465.1875
6465.1875 (1.05) = 6788.44688 --> after four years
6788.44688 + 1500 = 8288.44688
8288.44688 (1.05) = 8702.86922 --> after five years = $8702.87
23. If 25% of a number is 75. find the number.
A. 700 B. 600 C. 500 D, 400 E. 300
Answer:
23.E
Step-by-step explanation:
please click the heart and rate excellent and brainleist to ☻❤☺️☺️❤☻
Answer:
[tex]300 \\ \\ answer \: \: E\: \: is \: \: correct[/tex]
Step-by-step explanation:
Let the unknown number be x
[tex]x \times \frac{25}{100} = 75 \\ x = \frac{75 \times 100}{25} \\ x = 300[/tex]
Hope this helps you
Can I have the brainliest please?1. The local furniture store pays $140 for a chair and sells it with a
40% markup.
a. What is the markup?
b. What is the selling price of the chair?
Can u guys help and show the steps! pls thxs
Answer:
a. $56
b. $196
Step-by-step explanation:
a. Markup price
= 40% of 140
= 0.40*140
= $56
b. Selling Price
= $140 + $56
= $196
Terry's brother can paint a room in 3 hours less than Terry can paint it. Working together they can complete the job in 2 hours. How much time would require Terry to paint the room working alone? Enter just the number no words.
Answer:
6
Step-by-step explanation:
the equation would be 2/(x-3) + 2/x = 1 derived from the work formula of T/A + T/B = 1; T representing total time working together, A/B respectively representing the two different rates of working. In the end Terry would spend 6 hours working alone.
Using the following equation, complete the square and find the center and radius of the circle: x^2+ y^2 + 4x - 6y - 12 =0
Please help it’s a timed test
Answer:
Circle with the radius r=5 and the center (-2,3)
Step-by-step explanation:
Answer:
radius: 5 and center: (-2,3)
Step-by-step explanation:
The standard form of the equation after completing the square is
(x+2)^2+(y-3)^2=25
Write a unit rate for the situation $24 for 3 pounds
Solve the inequality: 4x-2<10
Answer:
w < 3
Step-by-step explanation:
One can solve an algebraic inequality just like how one solves an algebraic equation, by using inverse operations. The only major difference is that when one multiplies or divides by a negative number, one must remember to flip the inequality sign, this rule does not come into play in the given inequality.
4x - 2 < 10
+2 +2
4x < 12
/4 /4
w < 3
What is the median of this data set:
4, 2 ,5 ,7, 2 ,8, 5 ,6 ,6
Step-by-step explanation:
2 is the answer because it's in the middle
*****PLEASE HELP******
Which of the following is a parent function?
O A. f(x)=3^x - x/3
O B. f(x) = 2^x
O C. f(x) = 1/2 3 ^x
O D. f(x) = -3X^3 +1
Answer:
O B. f(x) = 2^x
i think its true but iam not sure
hope it helps
The fraction 1/2 and 3/6 are equal. True or False
Answer:
true
Step-by-step explanation:
3 is half of 6
1 is half of 2
Answer:
True
Step-by-step explanation:
Find the measure of angle x 125
Answer:
x = 125 degrees
Step-by-step explanation:
The vertical angles theorem states that two angles opposite to each other that are formed from 2 intersecting lines are congruent.
Therefore, angle x and the angle that is 125 degrees are congruent to each other.
So, x=125 degrees.
Hope this helps! :)
Corresponding Angles are congruent.
Which angle corresponds with <2?
Answer:
angle 4 and angle 8 are congruent
Answer:
[tex]\angle{6}\:corresponds\:\angle{2}[/tex]
I need with help with this question
Answer:
the answer is 3
Step-by-step explanation:
24 + m = 49 help plz
Answer: m=25
Step-by-step explanation: 49 - 24= 25
An equation is modeled below.
ООО
ОООО
ООООО
1
Key:
Which value of x would make the equation true?
O х = 6
OX 3
Oxe 1
Ox= 9
Answer:
x=6
Step-by-step explanation:
get your cup alone by removing the 3 balls. When I take one ball away from one side I have to take it form the other as well. so subtract 3 balls from both sides
x=6
I need help with this, please answer right I will give brainelist
Answer:
1 D. 400 spins
2 C.4/20
3 A. 6/20
Step-by-step explanation:
1
The more times you run a probability-based trial, the more likely you are to get close to the theoretical frequency.
2
Since 1 and 2 represent goals, just find the options that have three/four 2's and 1's. These are 5212, 2152, 2512, and 2112. Since there are 4 options out of 20, we can say our probability is 4/20
C
Since 1 and 2 represent goals, we have to find the options where there are no 1's or 2's. These are 6643, 3554, 4533, 6634, 4536, and 5546. Since there are 6 options out of 20, we can say our probability is 6/20
A carpenter worked for 4 days to finish a repair job.
She charged $825 for 15 hours of work.
What is the carpenter’s rate per hour?
A
$55
C
$85
B
$58
D
$182
What is the best estimate of the value of ln 16?
Answer:
6
Step-by-step explanation:
I think
Ms. Evans brought 240 crayons for her class.The crayons came in packs of 12.Howmany packs did she buy
Answer:
240/12=20
Step-by-step explanation:
Answer:
I think the answer is B
Step-by-step explanation:
There are 240 crayons.
The crayons came in packs of 12.
So, in order to find out how many packs she bought we have to divide 240 by 12.
240/12 = 20 packs
4. June's portfolio of stocks includes 177 shares of Parcher, 213 shares of Giaco
Household Goods, and 152 shares of Raxin Accounting. If Parcher pays yearly
dividend of $8.21 per share. Giaco Household pays $6.97 per share and Raxin
pays $11.44 per shares, how much does June earn in dividends per year?
I NEED AN ASNWER PLSS
Answer:
m=-3
Step-by-step explanation:
The volume of cracker boxes are normally distributed, with a mean of 7 oz and a standard deviation of 0.2 oz. If a box is selected at random, What is the probability of getting an amount between that is at least 7.5 oz
Answer:
0.0062 = 0.62% probability of getting an amount between that is at least 7.5 oz.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Mean of 7 oz and a standard deviation of 0.2 oz.
This means that [tex]\mu = 7, \sigma = 0.2[/tex]
What is the probability of getting an amount between that is at least 7.5 oz?
This is 1 subtracted by the pvalue of Z when X = 7.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{7.5 - 7}{0.2}[/tex]
[tex]Z = 2.5[/tex]
[tex]Z = 2.5[/tex] has a pvalue of 0.9938
1 - 0.9938 = 0.0062
0.0062 = 0.62% probability of getting an amount between that is at least 7.5 oz.
4. Jeanne has $17.50 in her piggy bank. How much money, m, does she need to buy a game that costs $68.75?
5. A number increased by 18 is 50.
6. A number when multiplied by 3 is -21
7. A number divided by -8 is 6
8. Ellen is x years old right now. In thirteen years she will be 24 years old. How old is she now?
9. Each piece of candy costs 0.25 cents. Sam bought a handful of candy and it costs a total of $2.00. How many pieces did he buy?
10. Suzanne made a withdrawal from her savings account. Her old balance was $350.72, and her new balance is $280.20. How much did she withdraw?
11. A large pizza has s, amount of slices that are split among 5 kids. The amount of slices each kid gets is 3. How many slices were there total?
Answer:
5)32
6)-7
7)-48
8)11
9)800
10)70.52
11)15
Step-by-step explanation:
Which conclusion can be drawn from the data?
Question 9 options:
For ten weeks, City A received less rainfall, on average, than City B.
The range between the maximum and minimum values for City B is greater than the range between maximum and minimum values for City A.
During the 10 wk period, the rainfall amount recorded most often for City B was 1 in.
The median for City A is less than the median for City B.
Answer:
During the 10 wk period, the rainfall amount recorded most often for City B was 1 in.
Step-by-step explanation:
Given the data :
City A :
Reordered data:
0, 0.2, 0.2, 0.3, 0.4, 1, 1.3, 1.5, 2.5, 3
City B :
Reordered data:
0, 0, 0.1, 0.1, 0.2, 0.3, 0.4, 1, 1, 1
Using a calculator :
Mean Rainfall for City A = 1.04
Mean rainfall for city B = 0.41
Range : maximum - minimum
City A = 3 - 0 = 3
City B = 1 - 0 = 1
Mode (most occurring) :
City A = 0.2
City B = 1
Median :
City A = 0.7
City B = 0.25
The only true conclusion in the options given that can be drawn from the data is that ;During the 10 wk period, the rainfall amount recorded most often for City B was 1 in.
Answer:
the Answer is C.
Step-by-step explanation:
I just took the test
greatest comon factor of 80 20
Answer:
The greatest common factor of 80 and 20 is 20
Step-by-step explanation:
(NO LINKS.)If two angles of an isosceles triangle are each 19.1°,
what is the measure of the 3rd angle? *** Remember
triangle angle sum.
Just help!!!! Please!!!!
Answer:
141.8
Step-by-step explanation:
the angles of a triangle add up to 180
180-19.1-19.1= 3rd angle
141.8
Plz Help! I'll put you Brainliest
Answer:
Step-by-step explanation:
Solve for x to the nearest degree.
Solve the system of equations.
3x + 5y = 9
3x + 2y = 3
A) x = 2, y = 3
B) x = 3, y = 2
C) x = - 1/3 , y = 2
D) x = 2, y = - 1/3
Answer: c
Step-by-step explanation: Slove for the first variable in on of the equations, then substitute the result into the other equation. giving you (-1/3, 2) or x=-1/3 and y= 2
?????????????????????
Answer:
5x^2 + 7x
option C is your answer