Finding the Fourth Proportional to 139,081.32, 191,906.56 and 81,730

Step by Step Solution

1. Step 1: Write the proportion equation
   139,081.32 : 191,906.56 = 81,730 : x
2. Step 2: Convert to fraction form
   139,081.32/191,906.56 = 81,730/x
3. Step 3: Cross multiply
   139,081.32x = 191,906.56 × 81,730
4. Step 4: Simplify right side
   139,081.32x = 15,684,523,148.80
5. Step 5: Solve for x
   x = 15,684,523,148.80/139,081.32
6. Step 6: Final answer
   x = 112,772.32