Finding the Fourth Proportional to 12,800.72, 19,209.79 and 7,855.27

Step by Step Solution

1. Step 1: Write the proportion equation
   12,800.72 : 19,209.79 = 7,855.27 : x
2. Step 2: Convert to fraction form
   12,800.72/19,209.79 = 7,855.27/x
3. Step 3: Cross multiply
   12,800.72x = 19,209.79 × 7,855.27
4. Step 4: Simplify right side
   12,800.72x = 150,898,048.89
5. Step 5: Solve for x
   x = 150,898,048.89/12,800.72
6. Step 6: Final answer
   x = 11,788.24