Finding the Fourth Proportional to 405,727.76, 608,605.50 and 139,485.98

Step by Step Solution

1. Step 1: Write the proportion equation
   405,727.76 : 608,605.50 = 139,485.98 : x
2. Step 2: Convert to fraction form
   405,727.76/608,605.50 = 139,485.98/x
3. Step 3: Cross multiply
   405,727.76x = 608,605.50 × 139,485.98
4. Step 4: Simplify right side
   405,727.76x = 84,891,934,600.89
5. Step 5: Solve for x
   x = 84,891,934,600.89/405,727.76
6. Step 6: Final answer
   x = 209,233.73