Finding the Fourth Proportional to 402,789.83, 555,838.22 and 221,501.57

Step by Step Solution

1. Step 1: Write the proportion equation
   402,789.83 : 555,838.22 = 221,501.57 : x
2. Step 2: Convert to fraction form
   402,789.83/555,838.22 = 221,501.57/x
3. Step 3: Cross multiply
   402,789.83x = 555,838.22 × 221,501.57
4. Step 4: Simplify right side
   402,789.83x = 123,119,037,288.50
5. Step 5: Solve for x
   x = 123,119,037,288.50/402,789.83
6. Step 6: Final answer
   x = 305,665.70