The domain is all real numbers, since x can be any number and create a y value
This can be written in a few ways, including:
X:X
X: R
-(infinity sign) is less than or equal to X is less than or equal to (infinity sign)
6 - 1/2z = 2/3
Steps
First, subtract 6 from both sides
6 - 1/2z - 6 = 2/3 - 6
Then, simplify
-1/2z = -16/3
Then, multiply both sides by -2
(-1/2z) (-2) = (-16/3) (-2)
Then, simplify
z = 32/3
For the first two,the probability is 0.4, and for # 3,the probability is .2