Finding the Fourth Proportional to 8,085.89, 12,129.18 and 2,821.43

Step by Step Solution

1. Step 1: Write the proportion equation
   8,085.89 : 12,129.18 = 2,821.43 : x
2. Step 2: Convert to fraction form
   8,085.89/12,129.18 = 2,821.43/x
3. Step 3: Cross multiply
   8,085.89x = 12,129.18 × 2,821.43
4. Step 4: Simplify right side
   8,085.89x = 34,221,632.33
5. Step 5: Solve for x
   x = 34,221,632.33/8,085.89
6. Step 6: Final answer
   x = 4,232.27