Looks like the PMF is supposed to be

which is kinda weird, but it's not entirely clear what you meant...
Anyway, assuming the PMF above, for this to be a valid PMF, we need the probabilities of all events to sum to 1:

Next,





If

, then

, where we take the positive root because we know

can only take on positive values, namely 1, 2, and 5. Correspondingly, we know that

can take on the values

,

, and

. At these values of

, we would have the same probability as we did for the respective value of

. That is,

Part (5) is incomplete, so I'll stop here.
Answer:
ok so this means 2/5 of the plant have germs and
5-2=3
so 3/5 plants are all good
5 times 20=100
3 times 20=60
so 60% of the plants have germs
Hope This Helps!!!
Answer:

Step-by-step explanation:
The point-slope form of a line is given by:

Where
(x_1,y_1) is the coordinate pair (any of the points given)
m is the slope. The ratio of change in y coordinates by x coordinates
Let's calculate the slope:

Now, it is given "y - 4", so y_1 is 4, so they are using the coordinate pair (7,4). So we can say x_1 = 7
Now we have all the values, lets write the equation:

This is the point-slope form.
2x + x - 1 x
= ------------------ * ---------
x(x - 1) 8
3x - 1
= --------------
8x - 8
Answer:
2.9456k is the correct answer