Finding the Fourth Proportional to 139,439.93, 192,411.45 and 78,997.63

Step by Step Solution

1. Step 1: Write the proportion equation
   139,439.93 : 192,411.45 = 78,997.63 : x
2. Step 2: Convert to fraction form
   139,439.93/192,411.45 = 78,997.63/x
3. Step 3: Cross multiply
   139,439.93x = 192,411.45 × 78,997.63
4. Step 4: Simplify right side
   139,439.93x = 15,200,048,534.86
5. Step 5: Solve for x
   x = 15,200,048,534.86/139,439.93
6. Step 6: Final answer
   x = 109,007.86