Answer:
2 hours
Step-by-step explanation:
Here you go. I hope you understand. Ask if you don't.
Answer:
Step-by-step explanation:
Given
See attachment for table
Required
Determine the average rate of change over 
Average rate of change is calculated using:
Where
In this case:
From the table:
The expression becomes
Since the sample size is less than 30, therefore we use
the t statistic.
Let us define the given variables:
N = sample size = 25
X = average score = 76
s = standard deviation = 12
99% Confidence interval
Degrees of freedom = n – 1 = 24
The formula for confidence interval is given as:
CI = X ± t * s / sqrt N
using the standard distribution table, the t value for DF
= 24 and 99% CI is:
t = 2.492
Therefore calculating the CI using the known values:
CI = 76 ± 2.492 * 12 / sqrt 25
CI = 76 ± 5.98
CI = 70.02, 81.98
Answer: The average score ranges from 70 to 82.
