Finding the Fourth Proportional to 385,365,093.86, 531,804,354.69 and 209,153,091.50

Step by Step Solution

1. Step 1: Write the proportion equation
   385,365,093.86 : 531,804,354.69 = 209,153,091.50 : x
2. Step 2: Convert to fraction form
   385,365,093.86/531,804,354.69 = 209,153,091.50/x
3. Step 3: Cross multiply
   385,365,093.86x = 531,804,354.69 × 209,153,091.50
4. Step 4: Simplify right side
   385,365,093.86x = 111,228,524,853,917,008
5. Step 5: Solve for x
   x = 111,228,524,853,917,008/385,365,093.86
6. Step 6: Final answer
   x = 288,631,551.29