Finding the Fourth Proportional to 388,510.50, 582,849.12 and 220,111.50

Step by Step Solution

1. Step 1: Write the proportion equation
   388,510.50 : 582,849.12 = 220,111.50 : x
2. Step 2: Convert to fraction form
   388,510.50/582,849.12 = 220,111.50/x
3. Step 3: Cross multiply
   388,510.50x = 582,849.12 × 220,111.50
4. Step 4: Simplify right side
   388,510.50x = 128,291,794,076.88
5. Step 5: Solve for x
   x = 128,291,794,076.88/388,510.50
6. Step 6: Final answer
   x = 330,214.48