Finding the Fourth Proportional to 139,035.62, 208,055.20 and 120,380.10

Step by Step Solution

1. Step 1: Write the proportion equation
   139,035.62 : 208,055.20 = 120,380.10 : x
2. Step 2: Convert to fraction form
   139,035.62/208,055.20 = 120,380.10/x
3. Step 3: Cross multiply
   139,035.62x = 208,055.20 × 120,380.10
4. Step 4: Simplify right side
   139,035.62x = 25,045,705,781.52
5. Step 5: Solve for x
   x = 25,045,705,781.52/139,035.62
6. Step 6: Final answer
   x = 180,138.77