Please see the attached file.

(A roulette wheel has 38 numbers: 18 red, 18 black, a 0, and a 00 (0 and 00 are neither red nor black). When the wheel is spun, all numbers are equally likely to be selected.)

What is the probability that the wheel lands on 0?
Total no of possibilities = 38
Total no of 0's = 2.
P(wheel landing on 0) = 2/38

A die is loaded so that the numbers 2 through 6 are equally likely to appear, but 1 is three times as likely as any other number to appear. One die is rolled. What is the probability of getting an even number?
P(2) =P(3) =P(4) = P(5) = P(6)
P(1) = 3P(2)
Sum of probabilities of all outcomes =1
Thus, 3P(2) + 5P(2) = 8P(2)=1
Thus, P(2)= P(3) =P(4) = P(5) = P(6) = 1/8 and P(1) = 3/8
What is the probability of getting an even number?
There are 3 possible even nos: 2,4,6
Probability of each even no = 1/8
Thus, P(even) = 3/8.

The dice are loaded so that the numbers 2, 4, and 6 are equally likely to appear. 1, 3, and 5 are also equally likely to appear, but 1 is three times as likely as 2 is to appear. One die is rolled. What is the probability of getting an even number?
P(2) =P(4) =P(6)
P(1) =P(3) =P(5)
P(1) = 3P(2)
Thus, 3P(2) + 3P(2) + 3P(2) + P(2) + P(2) +P(2) = 12P(2) =1
Thus, P(2) =P(4) =P(6) = 1/12
P(1) =P(3)=P(5) = 3/12
Probability of getting an even no = Sum of probability of even nos =P(2) +P(4) +P(6) =3/12
P(Even) = 3/12