Finding the Fourth Proportional to 85,505,298.72, 128,257,961.39 and 20,809,103.52

Step by Step Solution

1. Step 1: Write the proportion equation
   85,505,298.72 : 128,257,961.39 = 20,809,103.52 : x
2. Step 2: Convert to fraction form
   85,505,298.72/128,257,961.39 = 20,809,103.52/x
3. Step 3: Cross multiply
   85,505,298.72x = 128,257,961.39 × 20,809,103.52
4. Step 4: Simplify right side
   85,505,298.72x = 2,668,933,195,724,627.50
5. Step 5: Solve for x
   x = 2,668,933,195,724,627.50/85,505,298.72
6. Step 6: Final answer
   x = 31,213,658.52