Finding the Fourth Proportional to 385,307,494.18, 531,724,684.89 and 209,095,490.02

Step by Step Solution

1. Step 1: Write the proportion equation
   385,307,494.18 : 531,724,684.89 = 209,095,490.02 : x
2. Step 2: Convert to fraction form
   385,307,494.18/531,724,684.89 = 209,095,490.02/x
3. Step 3: Cross multiply
   385,307,494.18x = 531,724,684.89 × 209,095,490.02
4. Step 4: Simplify right side
   385,307,494.18x = 111,181,233,542,804,640
5. Step 5: Solve for x
   x = 111,181,233,542,804,640/385,307,494.18
6. Step 6: Final answer
   x = 288,551,962.32