Finding the Fourth Proportional to 206,463.59, 309,486.23 and 139,910.48

Step by Step Solution

1. Step 1: Write the proportion equation
   206,463.59 : 309,486.23 = 139,910.48 : x
2. Step 2: Convert to fraction form
   206,463.59/309,486.23 = 139,910.48/x
3. Step 3: Cross multiply
   206,463.59x = 309,486.23 × 139,910.48
4. Step 4: Simplify right side
   206,463.59x = 43,300,366,992.69
5. Step 5: Solve for x
   x = 43,300,366,992.69/206,463.59
6. Step 6: Final answer
   x = 209,723.99