Finding the Fourth Proportional to 139,072.94, 191,952.42 and 81,719

Step by Step Solution

1. Step 1: Write the proportion equation
   139,072.94 : 191,952.42 = 81,719 : x
2. Step 2: Convert to fraction form
   139,072.94/191,952.42 = 81,719/x
3. Step 3: Cross multiply
   139,072.94x = 191,952.42 × 81,719
4. Step 4: Simplify right side
   139,072.94x = 15,686,159,809.98
5. Step 5: Solve for x
   x = 15,686,159,809.98/139,072.94
6. Step 6: Final answer
   x = 112,790.88