Answer:
what
Step-by-step explanation:
Answer:
The confidence interval = (7.8 , 8.0)
Step-by-step explanation:
Confidence Interval formula =
Mean ± z × Standard deviation/√n
Mean = 7.9
Standard deviation = 0.9
n = number of samples = 164
z = z score of an 80% confidence interval = 1.282
Confidence Interval = 7.9 ± 1.282 × 0.9/√164
= 7.9 ± 0.0900966432
Confidence Interval
= 7.9 - 0.0900966432
= 7.8099033568
Approximately to 1 decimal place = 7.8
7.9 + 0.0900966432
= 7.9900966432
Approximately to 1 decimal place = 8.0
Therefore, the confidence interval = (7.8 , 8.0)
The right answers would be F,B,A
Do the equation 1200=500+11.50x
700=11.50x
Then divide 11.50 both sides
