Finding the Fourth Proportional to 22,399.32, 30,912.33 and 12,840.79

Step by Step Solution

1. Step 1: Write the proportion equation
   22,399.32 : 30,912.33 = 12,840.79 : x
2. Step 2: Convert to fraction form
   22,399.32/30,912.33 = 12,840.79/x
3. Step 3: Cross multiply
   22,399.32x = 30,912.33 × 12,840.79
4. Step 4: Simplify right side
   22,399.32x = 396,938,737.94
5. Step 5: Solve for x
   x = 396,938,737.94/22,399.32
6. Step 6: Final answer
   x = 17,721.02