I believe the answer is 5 because if however many times you can multiply 2.5 into 12.5, you get the answer of 5.
it would take him 32 minutes. You could use divisoin and multiplecation to figure it out
The other endpoint (x,y)
(X+18)/2 = 16 then x=14
(Y-18)/2 = -16 then y=-14