Step-by-step explanation:
2 objects and their shadows create 2 similar right-angled triangles.
that means all angles are the same, and the side lengths of one triangle correlate to the corresponding side lengths of the other triangle via the same factor.
so,
122 × f = 2
f = 2/122 = 1/61
therefore, Ryan is
305 × f = 305 × 1/61 = 5 ft
tall.