The correct answers are a,b,e,f
Answer:
There are about 80 students age 15 and above take a car to school.
Step-by-step explanation:
1. For all the columns the total has been given.
2. Bus is taken as 60 as walk/bike has been given 65 under age 15.
3. 195 row total Age 15 and above has been provided and updated.
4. Walk/Bike 152, 65 is already given Age 15 and above difference is 87.
5. Bus 60 under age 15 is already given total 110 difference is 50.
6. Age 15 and above 65,50,195 (Total) is already given row difference is 80.
7. Car is Age 15 and above is 80 and Total column is 98 difference is 18.
8. Age 15 and above take car is 80.
Answer:
Yes, we can conclude that average sales has changed.
Step-by-step explanation:
The null hypothesis, H0 : μ = 0.3
The alternative ; H0 : μ ≠ 0.3
The result of the 95% confidence interval of (.3095, .3275); This shows that the confidence interval is now between 30.95% and 32.75% ; since μ does not lie within the confidence interval value and the lower boundary of the confidence interval is > 30; we Can conclude with an evidence of 5% significance that his average sales as changed (increased).
We can reject H0 and conclude that μ > 0.3
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.
