Based on a sample of 100 employees a 95% confidence interval is calculated for the mean age of all employees at a large firm. The interval is (34.5 years, 47.2 years).
A. What was the sample mean?
B. Find the margin of error?
C. Find the critical value tc for:
a. a 90% confidence level when the sample size is 22.
b. an 80% confidence level when the sample size is 49.
Answer:
a
[tex]\= x = 40.85[/tex]
b
[tex]E = 5.85[/tex]
Ca
[tex]t_c = 2.08 [/tex]
Cb
[tex] t_c = 1.282 [/tex]
Explanation:
From the question we are told that
The sample size is n = 100
The upper limit of the 95% confidence interval is b = 47.2 years
The lower limit of the 95% confidence interval is a = 34.5 years
Generally the sample mean is mathematically represented as
[tex]\= x = \frac{a + b }{2}[/tex]
=> [tex]\= x = \frac{47.2 + 34.5 }{2}[/tex]
=> [tex]\= x = 40.85[/tex]
Generally the margin of error is mathematically represented as
[tex]E = \frac{b- a }{ 2}[/tex]
=> [tex]E = \frac{47.2- 34.5 }{ 2}[/tex]
=> [tex]E = 5.85[/tex]
Considering question C a
From the question we are told the confidence level is 90% , hence the level of significance is
[tex]\alpha = (100 - 90 ) \%[/tex]
=> [tex]\alpha = 0.10[/tex]
The sample size is n = 22
Given that the sample size is not sufficient enough i.e [tex]n < 30[/tex] we will make use of the student t distribution table
Generally the degree of freedom is mathematically represented as
[tex]df = n- 1[/tex]
=> [tex]df = 22 - 1[/tex]
=> [tex]df = 21[/tex]
Generally from the student t distribution table the critical value of [tex]\frac{\alpha }{2}[/tex] at a degree of freedom of 21 is
[tex]t_c =t_{\frac{\alpha }{2} , 21 } = 2.08 [/tex]
Considering question C b
From the question we are told the confidence level is 80% , hence the level of significance is
[tex]\alpha = (100 - 80 ) \%[/tex]
=> [tex]\alpha = 0.20[/tex]
Generally from the normal distribution table the critical value of [tex]\frac{\alpha }{2}[/tex] is
[tex] t_c =Z_{\frac{\alpha }{2} } = 1.282 [/tex]
What expression is equivalent to 12y + (7y)(3)
Answer:
I got 33y
Step-by-step explanation:
hi if its right but here
Answer:
57y
Step-by-step explanation:
you know that five pizzas will feed 20 people. how many pizzas do you need to order to feed 88 people?
A and B are independent events.
P(A) = 0.6
P(B) = 0.4
What is P(AB)?
O A. 0.24
O B. 0.6
O C. 0.4
D. Not enough information
Answer:
Not enough information
Bismuth-214 has a half-life (50%) of approximately 20 minutes. Find the amount of Bismuth-214 left
from a 40-gram sample after 2 hours.
Answer: 3.36
Step-by-step explanation:
f(x)=214(1-.50)^6 6= amount of times 20 min goes into 2 hrs
f(x)=214(.50)^6
.5^6=.0157
f(x)=214(.0157)
3.36
Which of the following are two-step equations? Choose more than
one answers
Answer:
i think a b d f
Step-by-step explanation:
A sporting goods store sells two types of bicycles, in two colors. The table
shows its sales over the last year.
Road bike
Mountain bike
Total
Silver
81
39
120
Black
54
26
80
Total
135
65
200
Are buying a road bike and buying a silver bike independent events?
A. Yes, because P(road bike) = 0.675 and P(road bike | silver) = 0.675.
B. No, because P(road bike) = 0.675 and P(road bike | silver) = 0.6.
C. Yes, because P(road bike) = 0.405 and P(road bike | silver) = 0.675.
O D. No, because P(road bike) = 0.675 and P(road bike | silver) = 0.675.
Answer:
Answer D
Step-by-step explanation:
120 + 81+ 39=240 silver bikes
80+54+26= 160 black bikes
Total 200 + 135 + 65= 400
240+ 160=400
Answer:
Answer is C
Step-by-step explanation:
ap3xxx
i am a decimal number less than 1. the digit in my tenths place is an even prime number. my hundredths digit is twice my tenths digit, and my hundred thousandths digit is twice my hundredths digit. the thousandths digit is three less than my hundredths digit. my ten thousandths digit is the sum of my tenths and thousandths digit. what number am i?
Answer:
.
Step-by-step explanation:
Answer:
0.24857
Step-by-step explanation:
Less than 1 is 0. and
only even prime is 2
2x - y = -2,X + y = -1
Answer:
x=-1, y=0
Step-by-step explanation:
Hope this is right!!
find the value of x then classify the triangle by its angles
Answer:
x = 134°
Step-by-step explanation:
Let
[tex]\angle A=64^{\circ}\\\\\angle B =70^{\circ}[/tex]
We need to find the value of x.
We can see from the figure that x is exterior angle. To find x we can use exterior angle theorem. According to this theorem,
[tex]x=\angle A+\angle B\\\\x=64+70\\\\x=134^{\circ}[/tex]
Hence, the value of x is 134°
Black friday sale on TVs were 50 in tv for $148.00 or 65 in for $199.00 which is the better buy this is not worth a grade just some understanding
Answer:
i personally think the 65 in. one
Step-by-step explanation:
What is the range in interval notation?
Answer:
The blue box
Step-by-step explanation:
Youre talking about range which takes place on the y-axis (domain is the x-axis).
The top point is an open circle which indicates in the math world the parentheses and the bottom point 1 in a bracket as its a closed circle.
Convert 4/16 to a decimal.
0.1
O
0.25
0.5
0.75
Answer:
0.25
How to Solve:
Take the denominator of 4/16 and find a number to make it 10, 100, any one followed by zeroes:
16 x 6.25 = 100
Do the same to the numerator:
4 x 6.25 = 25
Now, take 25 and take a decimal point two spaces to the right:
0.25
How many ways are there to rearrange the letters ALIVE in such a way that the word EVIL is not contained in the resulting word
Answer: 118 combinations.
Step-by-step explanation:
In ALIVE we have 5 letters, rearranging it we have the possible options of:
5 options for the first letter.
4 options for the second letter, as one was already chosen for the first one
3 options for the third letter, as 2 were already chosen.
2 options for the fourth letter.
1 option for the last letter.
The total number of combinations will be equal to the product of the numbers of options for each letter, then we have:
5*4*3*2*1 = 120 combinations.
And the combinations where the word EVIL is formed are:
AEVIL
EVILA
2 combinations, then the total number of combinations such that the word evil is not formed are:
120 - 2 = 118 combinations.
if f(x) = x^2 + x , find f(-3) a)-12 b)3 c)6
In a certain chemical, the ratio of zinc to copper is 4 to 19. A jar of the chemical contains 760 grams of copper. How many grams of zinc does it contain?
1) 760 grams
2) 3,610
3) 30,400
4) 190 or 160 grams
Could someone help me pls with this question it is math !
Answer:
B) 275n + 1000 = 2700
Step-by-step explanation:
n is just a placer holder for how many days the Carter family can vacate.
That being said, the question says that they will spend 275 per day, which is per n. You want to multiply 275 by n.
Then the question says it plans to spend $1000 on meals (that's a lot). Instead of substracting, you are going to add for this equation. You want the equation to match; you want both sides to equal 2700 so you can determine how many days you can spend there.
using the order of operations, what should be done first to evaluate 8² + 10 (-5) (3) - 5?
A. Subtract 5 From 3.
B. Divide 10 by -5.
C. Add 6 and 10.
D. Evaluate 8².
Answer:
D
Step-by-step explanation:
if you answer this you are a genius.
Answer:
Question 1: 3380g
Question 2: 2g/cm^3
Step-by-step explanation:
I used online mass and density calculators. Hope this helps :)!
I will give brainliest
The original Ferris wheel introduced at the 1893 World’s Fair in Chicago had a diameter of 125 feet. What is the approximate distance traveled by a person who rode this Ferris wheel for 5 complete revolutions? Use 3.14 for pi to solve.
1,962.5 ft
981.25 ft
625 ft
392.5 ft
Answer:
B is the answer to your question!
1 Diego cut 7 smaller boards of equal length from a board that is 9 1/3 feet long. How long is each of the 7 smaller boards?
Answer:
4\3
Step-by-step explanation:
Answer:
4/3
Step-by-step explanation:
because if you caculate right and do the answer correctly it is D. thanks can i get brainlest.
max is thinking of a number which he calls n
Answer:
what are you trying to ask?
Step-by-step explanation:
What is 1/32 as a decimal
Answer:
0.03125
Hope this helps! :)
0.03125 is the answer :) hope it helped
Can someone help me on these questions?
Answer:
I can give you a few of them, sorry
Step-by-step explanation:
5) obtuse 6)straight 7)right 9) 24°
Please explain how to do this please show work
Answer:
(x-1)(x+4)
I.e x(x+4)-1(x+4)
Xsquare +4x -x -4
Xsquare +3x -4
which could be the name of a plane?
Answer: where are the options?
Step-by-step explanation:
Answer:
There is not enough information presented to give an answer
Step-by-step explanation:
If you add more information, I will try and answer it for you
A recipe calls for 3 cups of water for every 4 cups of flour.
What is the unit rate of water to flour, written as a decimal?
A grocery store has bananas on sale for 2 pounds for $1.50. What is the cost of 6 pounds of bananas?
Answer:
$4.50
Step-by-step explanation:
6 / 2 = 3
$1.50 x 3 = $4.50
Understanding how a budget is created will help you develop good financial decision making skills. This is known as: Question 3 options: Financial expertise Financial literacy Accounting Math
Answer:
True mate
Step-by-step explanation:
The budget is created to develop good financial decision-making skills, is known as Financial literacy. Thus, option 2nd is correct.
What is Budget?Budget refers to the blueprint of the expenses and income of the individual or the corporation. It is the estimation of the net revenue after deducing all losses and expenses for the specific period of time. After the expiry of the specific period, the new budget is prepared.
Government also prepares the budget to calculate the deficit or surplus in the government spending. Therefore, It can be prepared by a person, group, business or government organization.
Financial literacy refers to confident of understanding the concepts regarding the finances of the person and his savings. It is study about the money related affairs.
Therefore, it can be concluded that option 2nd is correct.
Learn more about Budget here:
https://brainly.com/question/17198039
#SPJ2
2+2jjjjjjkkkkkkuyuoo
Answer:
4
Step-by-step explanation:
1+1+1+1=2+2=4