1answer.
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
r-ruslan [8.4K]
2 years ago
11

A sportswriter wishes to see if a football filled with helium travels farther, on average, than a football filled with air. To t

est this hypothesis, the writer uses 18 male subjects, randomly divided into two groups of 9 subjects each. Group 1 kicks a football filled with helium to the recommended pressure, while Group 2 kicks a football filled with air to the same pressure. The sample mean yardage for Group 1 was barx2 = 30 yards with a standard deviation of s1 = 8 yards. The mean yardage for Group 2 was barx2 = 25 yards with a standard deviation of s2 = 6 yards. Assume that the two groups of kicks are independent. Let μ1 and μ2 represent the mean yardage we would observe for the entire population represented by the volunteers if all members of this population kicked, respectively, a helium-filled football and an air-filled football. Let σ1 and σ2 be the corresponding population standard deviations. Assuming two-sample t procedures are safe to use, what is a 99% confidence interval for μ1 – μ2?
A) 4 ± 7.7 yards.B) 4 ± 11.2 yards.C) 4 ± 4.7 yards.D) 4 ± 6.2 yards.
Mathematics
1 answer:
Sphinxa [80]2 years ago
4 0

Answer:

5 ± 9.74

Step-by-step explanation:

Confidence interval, two - sample, t procedure ;

μ1 - μ2 = (x1 - x2) ± Tcritical*S

S = sqrt[(s1²/n1) + (s2²/n2)]

n1 = 9 ; n2 = 9 ; s1 = 8 ; s2 = 6 ; x1 = 30 ; x2 = 25

S = sqrt[(8^2/9) + (6^2/9)]

S = sqrt[11.111111]

S = 3.333

Tcritical at 99% confidence interval

df = 18 - 2= 16

Tcritical = 2.92

(30 - 25) ± 2.92*(3.333)

5 ± 9.74

You might be interested in
You can pay $4.80 for 8 pounds of sugar or $11.75 for 25 pounds of
cricket20 [7]
25 pounds would be a better deal
7 0
2 years ago
Read 2 more answers
Plz help, i will give brainliest?<br><br> what is 890,754 x 205,789
nikdorinn [45]

Answer:

183,307,374,906

3 0
2 years ago
Read 2 more answers
four students have to give a speech in class today. In how many different orders can they give their speeches?
bulgar [2K]

Answer:

There are 24 possible outcomes.

Step-by-step explanation:

1. 1-2-3-4

2. 1-4-3-2

3. 1-4-2-3

4. 1-2-4-3

5. 1-3-2-4

6. 1-4-3-2

7. 2-4-3-1

8. 2-1-3-4

9. 2-1-4-3

10. 2-4-1-3

11. 2-3-1-4

12. 2-3-4-1

13. 3-2-1-4

14. 3-2-4-1

15. 3-1-2-4

16. 3-1-4-2

17. 3-4-1-2

18. 3-4-2-1

19. 4-3-2-1

20. 4-3-1-2

21. 4-2-3-1

22. 4-2-1-3

23. 4-1-2-3

24. 4-1-3-2

Hope this helps!!


5 0
2 years ago
How 2 do?<br><br> (n)(n+7)(n+8)
madreJ [45]

Answer:

n^{3} + 15n^{2} + 56n

Step-by-step explanation:

First FOIL  (n + 7)(n + 8) and then distribute n

(n + 7)(n + 8) = n^{2} +15n + 56

 n (n^{2} +15n + 56)

= n^{3} + 15n^{2} + 56n

6 0
2 years ago
Find | P |<br><br> a. 15<br> b. 22<br> c. 24<br> d. 8
ankoles [38]

Answer:

c. 24

Step-by-step explanation:

15+9=24

5 0
3 years ago
Other questions:
  • the length of the base of an isosceles triangle is x. The length of a leg is 4x-5. The terminator of the triangle is 35. find x.
    11·1 answer
  • Why is triangle ABL ≃ triangle BAE?<br> A. SSS<br> B. SAS<br> C. ASA
    9·1 answer
  • In standard notation 208.06 is written as
    5·2 answers
  • Nathan opens a new savings account and makes an initial deposit of $400.
    15·1 answer
  • 3 gallons of batter are poured equally into 4 bowls. How many gallons of batter are in each bowl?
    9·1 answer
  • What’s the reciprocal of the number 1 1/2?
    14·1 answer
  • Which statement about this figure is true?????
    5·1 answer
  • SOMEONE PLEASE HELP MEEEEE3​
    13·1 answer
  • There is 12 inches in a whole hole how many inches is in a half of a hole?
    6·2 answers
  • 5(2 + 5) = 6 − 10 – solve for x please show your work
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!