Answer:
Step-by-step explanation:
Answer:
29.1
Step-by-step explanation:
Use logic.
Jk. Tan(x) = 5/9 so x = tan^-1(5/9)
Use a graphing calculator in degrees mode.
Answer:
w = -9
Step-by-step explanation:
7/3w + 19 = -2
-19 -19
7/3w = -21
Divide both sides by 7/3
w = -9
Answer:
This is cluster sampling.
Step-by-step explanation:
American Airlines randomly selects 110 flights during a certain week and surveys all passengers on the flights.
This is a type of cluster sampling.
This type of sampling is done by dividing the population into different groups and a simple random sample of clusters is selected from the population.
Answer:
(130.08, 139.92)
Step-by-step explanation:
Given that:
Mean (m) = 135
Standard deviation (σ) = 30
Sample size (n) = 100
α = 90%
The confidence interval value is obtained using the relation:
Mean ± Zcritical * (standard deviation / sqrt(n))
Zcritical at 90% = 1.64
standard deviation / sqrt(n) = 30 / sqrt(100)
= 30 / 10 = 3
Hence,
135 ± 1.64 * (3)
Lower limit : 135 - (1.64 * 3) = 130.08
Upper limit : 135 + (1.64 * 3) = 139.92
Hence,
Confidence interval = (130.08, 139.92)