The number of cars for each household is:
2 0 1 2 3 2 1 0 1 4
1 3 2 0 1 1 2 3 1 2
1 0 2 2 1 2 2 1 0 2
Getting the average of this will give us: 45/30 = 1.5
So n is 30
Standard deviation is: 1.00858
95% confidence level is equal to 1.960 z value
So, confidence interval is calculated by: mean ± z s/ √n
So plugging in our data:
= 1.5 ± (1.960) 1.00858/ √30
= 1.5 ± (1.960) 0.184140672
= 1.5 ± 0.360915717
= 1.14 < x < 1.8
Therefore, the answer is A.
