Answer:
Events E and F are independent.
Step-by-step explanation:
E = {multiple of 3} = {3, 6, 9, 12}
P(E) = 4/12
F = {even number} = {2, 4, 6, 8. 10, 12}
P(F) = 6/12
E and F = {even and multiple of 3} = {6, 12}
P(E∩F) = 2/12
In order for two events to be independent the following relationship must be true:

Testing this property:

The relationship holds true, thus events E and F are independent.
Answer:
3
Step-by-step explanation:
In order to rationalize the denominator of each expression, we need to multiply the expression by the same radical in the denominator, this way we can remove the radical from the denominator.
9)

10)

11)

12)
Answer:
a) 96% CI: 
b) If we estimate that the fraction of voters is 0.57, we can claim with 96% confidence that the error is equal or less than 0.06 from the estimated proportion.
Step-by-step explanation:
The proportion of the sample is

The standard deviation of the sample proportion is

For a 96% CI, the z-value is z=1.751.
Then, the 96% CI can be written as:

b) If we estimate that the fraction of voters is 0.57, we can claim with 96% confidence that the error is equal or less than 0.06 from the estimated proportion.
The correct answer is 48%
There are 10 even numbers from 1 to 21.
That makes the probability of an even number 10 out 21.
10 / 21 x 100 = 48%