Answer:
a)
90% confidence interval for the mean grading time of all composition papers.
(12.47981 , 13.52019)
b)
Appropriate inequality
The interval is ( 12.47981 < μ < 13.52019)
Step-by-step explanation:
<u><em>Explanation</em></u>:-
a)
Given sample size 'n' = 40
Mean of the sample = 13 minutes
standard deviation = 2 min
level of significance = 0.10 or 90%
90% confidence interval for the mean grading time of all composition papers.


( 13 - 0.52019 , 13 + 0.52019)
(12.47981 , 13.52019)
b)
The interval is ( 12.47981 < μ < 13.52019)
<span>8 ≥ 16y
Divide both sides by 16.
0.5 </span>≥ y, or y ≤ 0.5.
The answer is A) y ≤ 0.5.
Answer:
-8
Step-by-step explanation:
x less than or equals to -8
Answer:
7.2+x=19.5
x=19.5-7.2
x=12.2
Step-by-step explanation: