They equal different things. If you simplify the second equation, it is 15x-4 = 15x-12 because of the 3 outside of the paranthesis. Therefore, the equation is wrong.
Answer:
Step-by-step explanation: Opposite sides of a parallelogram are equal.
Answer:
a) Mean = 2.6
B) Variance = 9.2
Step-by-step explanation:
We are given the following probability mass function in the question:

a) Mean of random variable

b) Variance of the random variable

Answer:
16
Step-by-step explanation:
8+8
B.
because {1,1,3,5,8}
{2,2,4,6,9}
you're just counting the numbers after the one that was given to you.