Finding the Fourth Proportional to 138,134.77, 207,592.17 and 81,985.37

Step by Step Solution

1. Step 1: Write the proportion equation
   138,134.77 : 207,592.17 = 81,985.37 : x
2. Step 2: Convert to fraction form
   138,134.77/207,592.17 = 81,985.37/x
3. Step 3: Cross multiply
   138,134.77x = 207,592.17 × 81,985.37
4. Step 4: Simplify right side
   138,134.77x = 17,019,520,866.55
5. Step 5: Solve for x
   x = 17,019,520,866.55/138,134.77
6. Step 6: Final answer
   x = 123,209.54