Answer:

Step-by-step explanation:
The formula of a midpoint of a segment AB with endpoints at A(x₁, y₁) and B(x₂, y₂):

We have the points P(-6, 3) and Q(9, -11).
Substitute:

Answer:
8
Step-by-step explanation:
Some guy had the answer key
In general, the most probable distribution is in the ratio of the respective types, namely
Number of blue tails
=12*(53/(53+40))
=6.84
To check between 6 or 7, we use the hypergeometric distribution:
P(B=6)
=C(40,6)C(53,6)/(C(93,12)
=3838380*22957480/416579843773639
=0.211530
P(B=7)
=C(40,5)C(53,7)/(C(93,12)
=658008*154143080/416579843773639
=65563917120/269282381237
=0.243476
Hence the most probable number of blue tail fishes is 7
Note: it would be prudent to calculate P(B=8)=0.194443 to show that P(B=7) is indeed the highest value.