2:3. 2+3=5. So 45 divided by 5 equals 9
9x2 ( the ratio number of country music is 2)
So there are 18 country albums in the collection
Answer:
Its B
Step-by-step explanation:
Answer:
1) 1:10
2) 150:2
3) 1:3
4) 20hrs : 1hrs
Step-by-step explanation:
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)