answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Eduardwww [97]
2 years ago
6

A nationwide survey of 100 boys and 50 girls in the first grade found that the daily average number of boys who are absent from

school is 15, with a standard deviation of 7. For girls, the average number of absentees is 10, with a standard deviation of 6. The standard deviation of the difference is
Mathematics
2 answers:
dusya [7]2 years ago
6 0
Te difference of 2 standard deviation of a population n1 & n2 is given by the formula:
sigma (difference)=√(sigma1/n1 + sigma2/n2), Plug:

sigma(d)= √(49/100 + 36/50)

Sigma(d=difference) =1.1

Gala2k [10]2 years ago
5 0

Find the mean difference (male absences minus female absences) in the population.

μd = μ1 - μ2 = 15 - 10 = 5

Find the standard deviation of the difference.

σd = sqrt( σ12 / n1 + σ22 / n2 )

σd = sqrt(72/100 + 62/50) = sqrt(49/100 + 36/50) = sqrt(0.49 + .72) = sqrt(1.21) = 1.1

Find the z-score that produced when boys have three more days of absences than girls. When boys have three more days of absences, the number of male absences minus female absences is three. And the associated z-score is

z = (x - μ)/σ = (3 - 5)/1.1 = -2/1.1 = -1.818

Find the probability. This problem requires us to find the probability that the average number of absences in the boy sample minus the average number of absences in the girl sample is less than 3. To find this probability, we enter the z-score (-1.818) into Stat Trek's Normal Distribution Calculator. We find that the probability of a z-score being -1.818 or less is about 0.035


You might be interested in
In a new card game, you start with a well-shuffled full deck and draw 3 cards without replacement. If you draw 3 hearts, you win
lyudmila [28]

Answer:

Expected pay winning $50= $0.585

Expected pay winning $25= $2.36

Expected pay for anything else= $-4.35

Expected returns=3.59

Expected value for one play= $(-1.41)

Do not play this game because you will lose $1.41

Step-by-step explanation:

Probability P(3 hearts) = (13/52)×(12/51)×(11/50) = 0.013

Probability P(3black)= (26/52)×(24/51)×(23/50) = 0.118

Probability P(drawing anything else)= 1 - 0.013 - 0.118= 0.869

Expected pay($50)= 0.013$(50-5)= $ 0.585

Expected pay($25)= 0.118(25-5)$ = $2.36

Expected pay for anything else= 0.869(0-5)$ =$(-4.347)

Expected value of one play=$ (0.585 + 2.353 -4.347) = -$1.41

c) Do not play the game.

6 0
1 year ago
Which equation finds the volume of a cube with a side length of 2 n Superscript 6 units?
elena-14-01-66 [18.8K]

Answer:

Volume of the cube: 8n^{18}

Step-by-step explanation:

A cube is a solid figure consisting of 6 squared faces arranged in a structure at right angle with each other.

The volume of a cube is given by:

V=L^3

where

V is the volume

L is the length of one side of the cube

In this problem, the length of the side of the cube is

L=2n^6

Therefore, the volume of the cube is

V=(2n^6)^3 = 2^3 (n^6)^3 = 8n^{18}

7 0
1 year ago
Read 2 more answers
Jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50, while the 16 oz. box cos
zhannawk [14.2K]
X + y = 24...y = 24 - x
3.50x + 5.00y = 97.50

3.50x + 5(24 - x) = 97.50
3.50x + 120 - 5x = 97.50
3.50x - 5x = 97.50 - 120
-1.5x = -22.50
x = -22.50/-1.5
x = 15....there were 15 ten oz boxes (x) sold
3 0
2 years ago
Read 2 more answers
It takes 5 carpenters 5 hours to make 5 chairs. How long would it take 100 carpenters to make 100 chairs?
Elza [17]
I hour because, one of the 5 carpenters built one chair in one hour, so one of the 100 carpenters would build one chair in one hour, there are only 95 more carpenters, nothing else different.
Hope I helped!
7 0
2 years ago
Read 2 more answers
Which quadratic equation is equivalent to (x2 – 1)2 – 11(x2 – 1) + 24 = 0? u2 – 11u + 24 = 0 where u = (x2 – 1) (u2)2 – 11(u2) +
Vinvika [58]
<span><span>u2</span> – 11u + 24 = 0 where u = (x2 – 1) the first awnser, a.</span>
4 0
1 year ago
Read 2 more answers
Other questions:
  • Which expression is equivalent to i 233
    6·2 answers
  • The price of a 200000 home listed by remax was reduced by 1/20. What is the new price?
    9·1 answer
  • Tara and Levi are trying to decide between homeowners insurance policies offered by two different agencies. AAA Insurance has of
    9·2 answers
  • SOMEONE PLEASE HELP ME ASAP!!!
    6·1 answer
  • Charlotte's annual salary is 29,354 dollars. She is hoping to win the World Lottery which has a grand prize of 6,156,782,221 dol
    12·2 answers
  • In the trapezoid at the right, BE= 2x-8, DE= x-4, and AC= x+2
    13·1 answer
  • The sum of two numbers is 90. The larger number is 14 more than 3 times the smaller number. Find the numbers
    9·1 answer
  • A side of a regular six - sided polygon is 8cm long. The perimeter of a similar polygon is 60cm. What is the length of a side of
    12·1 answer
  • There were 125 females and 100 males present at the high school pep rally. Find the ratio of males to the total number of people
    12·1 answer
  • Calculate the standard deviation. Variance = 107.76. Mean = 34.2
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!