Finding the Fourth Proportional to 3,855.12, 5,786.34 and 1,908.72

Step by Step Solution

1. Step 1: Write the proportion equation
   3,855.12 : 5,786.34 = 1,908.72 : x
2. Step 2: Convert to fraction form
   3,855.12/5,786.34 = 1,908.72/x
3. Step 3: Cross multiply
   3,855.12x = 5,786.34 × 1,908.72
4. Step 4: Simplify right side
   3,855.12x = 11,044,502.88
5. Step 5: Solve for x
   x = 11,044,502.88/3,855.12
6. Step 6: Final answer
   x = 2,864.89