Answer:
1/4
Step-by-step explanation:
3/12=
3÷3/12÷3=
1/4
40=1.5f+2.25c, please mark brainiest and give it a heart (:
Answer:C. (77.29, 85.71)
Step-by-step explanation:
We want to determine a 95% confidence interval for the mean test score of randomly selected students.
Number of sample, n = 25
Mean, u = 81.5
Standard deviation, s = 10.2
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes
81.5 +/- 1.96 × 10.2/√25
= 81.5 +/- 1.96 × 2.04
= 81.5 +/- 3.9984
The lower end of the confidence interval is 81.5 - 3.9984 =77.5016
The upper end of the confidence interval is 81.5 + 3.9984 =85.4984
Therefore, the correct option is
C. (77.29, 85.71)
3.4 x 10^8 is the answer m888888888888888
