Finding the Fourth Proportional to 388,110.72, 535,590.72 and 218,345.92

Step by Step Solution

1. Step 1: Write the proportion equation
   388,110.72 : 535,590.72 = 218,345.92 : x
2. Step 2: Convert to fraction form
   388,110.72/535,590.72 = 218,345.92/x
3. Step 3: Cross multiply
   388,110.72x = 535,590.72 × 218,345.92
4. Step 4: Simplify right side
   388,110.72x = 116,944,048,501.86
5. Step 5: Solve for x
   x = 116,944,048,501.86/388,110.72
6. Step 6: Final answer
   x = 301,316.20