Answer:
b. $28
Step-by-step explanation:
We have these following probabilities:
0.4 = 40% probability of $40
0.2 = 20% probability of $30
0.2 = 20% probability of $20
0.2 = 20% probability of $10
The expected value is:
We multiply each value by its probability. So

So the correct answer is:
b. $28
(7x^2-3x)+4x^2
7x^2+4x^2-3x
11x^2-3x
Answer: 11x^2-3x.
You just combine like terms.
F(0)=3. That means when the x input is 0, the y output, the y coordinate, is 3. It will be a point on the graph of whatever that curve looks like.