Finding the Fourth Proportional to 219,443.80, 329,136.52 and 86,288.30

Step by Step Solution

1. Step 1: Write the proportion equation
   219,443.80 : 329,136.52 = 86,288.30 : x
2. Step 2: Convert to fraction form
   219,443.80/329,136.52 = 86,288.30/x
3. Step 3: Cross multiply
   219,443.80x = 329,136.52 × 86,288.30
4. Step 4: Simplify right side
   219,443.80x = 28,400,630,778.72
5. Step 5: Solve for x
   x = 28,400,630,778.72/219,443.80
6. Step 6: Final answer
   x = 129,420.98