Hello,

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Answer:
endpoint is (29, -13)
Step-by-step explanation:
Formula for midpoint is 
So, let
be the coordinates of the endpoint you are looking for.
and
= (10, -3)

-9 +
= 20 7 + 

endpoint is (29, -13)
The probabillity can be found by using binomial probability formular considering that the event is discrete in nature and there are two possiple outcomes.