Finding the Fourth Proportional to 81,411.30, 122,138.55 and 28,815.30

Step by Step Solution

1. Step 1: Write the proportion equation
   81,411.30 : 122,138.55 = 28,815.30 : x
2. Step 2: Convert to fraction form
   81,411.30/122,138.55 = 28,815.30/x
3. Step 3: Cross multiply
   81,411.30x = 122,138.55 × 28,815.30
4. Step 4: Simplify right side
   81,411.30x = 3,519,458,959.82
5. Step 5: Solve for x
   x = 3,519,458,959.82/81,411.30
6. Step 6: Final answer
   x = 43,230.60