Answer:


Now we can find the expected value with this formula:

And replacing we got:

Step-by-step explanation:
For this case we know the following probability mass function given:

For this case we need to satisfy the following condition in order to have a probability distribution function:

And we have this:


Now we can find the expected value with this formula:

And replacing we got:

0.735 expressed as a fraction is 3/8
Answer:
16/21
Step-by-step explanation: