Finding the Fourth Proportional to 12,904.38, 17,811.83 and 8,428.77

Step by Step Solution

1. Step 1: Write the proportion equation
   12,904.38 : 17,811.83 = 8,428.77 : x
2. Step 2: Convert to fraction form
   12,904.38/17,811.83 = 8,428.77/x
3. Step 3: Cross multiply
   12,904.38x = 17,811.83 × 8,428.77
4. Step 4: Simplify right side
   12,904.38x = 150,131,839.42
5. Step 5: Solve for x
   x = 150,131,839.42/12,904.38
6. Step 6: Final answer
   x = 11,634.18