Finding the Fourth Proportional to 139,082.32, 191,907.94 and 81,731

Step by Step Solution

1. Step 1: Write the proportion equation
   139,082.32 : 191,907.94 = 81,731 : x
2. Step 2: Convert to fraction form
   139,082.32/191,907.94 = 81,731/x
3. Step 3: Cross multiply
   139,082.32x = 191,907.94 × 81,731
4. Step 4: Simplify right side
   139,082.32x = 15,684,827,844.14
5. Step 5: Solve for x
   x = 15,684,827,844.14/139,082.32
6. Step 6: Final answer
   x = 112,773.70