Finding the Fourth Proportional to 13,697.31, 18,901.98 and 7,728.83

Step by Step Solution

1. Step 1: Write the proportion equation
   13,697.31 : 18,901.98 = 7,728.83 : x
2. Step 2: Convert to fraction form
   13,697.31/18,901.98 = 7,728.83/x
3. Step 3: Cross multiply
   13,697.31x = 18,901.98 × 7,728.83
4. Step 4: Simplify right side
   13,697.31x = 146,090,095.57
5. Step 5: Solve for x
   x = 146,090,095.57/13,697.31
6. Step 6: Final answer
   x = 10,665.60