Answer:
The answer to your question is 12.55 cm
Step-by-step explanation:
Data
Adam                  Cara
height = 159 cm          height = 140 cm
shadow = 105 cm         shadow = x
Process
1.- To solve this problem use the Thales' theorem
     Cara's shadow / Cara's height = Adam's shadow / Adam's height
- Substitution
                   x / 140 = 105 / 159
-Solve for x
                   x = 105 (140) / 159
-Simplification
                   x = 14700 / 159
                   x = 92.45 cm
Cara's shadow is 92.45 cm long.
2.- If both shadows are in line, then Cara must walk forward
        105 - 92.45 cm
        12.55 cm
      Â