The answer to your question is 5.100
The left figure that is 2.5 is taken as numerator while the right figure that is 3.15 is take as denominator.
therefore the fraction is
2.5/3.15
the multiply by a 100 to remove the decimals to give
250/315
in simplest form the fraction is divided by 5 to give
50/63
Any ratio equal to 5:9 i.e., 10:18, 15:27, 20:36, etc.
Just multiply 5 and 9 by the same thing.
The intersecting chords theorem states that whenever two chords intersect, the product of their pieces is constant.
So, in this case, we have

Plugging your values, we have

This equation has solutions
, but we can't choose
, because it would lead to

So, the only feasible solutions is 