Answer:

Step-by-step explanation:
We can prove that a tangent will always be perpendicular to the radius touching it. So, the other angle in the diagram is
.
Because all the angles of a triangle sum to
, we have that
.
We combine like terms on the left side to get
.
We subtract
on both sides to get
.
So,
and we're done!
I divided 5 by 9 and multiplied it by 100 to get the percentage for the probability the horse will win. I got 55.55%. I subtracted 55.55 from 100 and got 44.45% chance of not winning the race.
Just work backwards.
342.5/ 34.25 = 10