Finding the Fourth Proportional to 139,391.96, 209,013.81 and 55,148.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139,391.96 : 209,013.81 = 55,148.72 : x
2. Step 2: Convert to fraction form
   139,391.96/209,013.81 = 55,148.72/x
3. Step 3: Cross multiply
   139,391.96x = 209,013.81 × 55,148.72
4. Step 4: Simplify right side
   139,391.96x = 11,526,844,083.82
5. Step 5: Solve for x
   x = 11,526,844,083.82/139,391.96
6. Step 6: Final answer
   x = 82,693.75