Finding the Fourth Proportional to 22,540.78, 31,108.46 and 12,981.06

Step by Step Solution

1. Step 1: Write the proportion equation
   22,540.78 : 31,108.46 = 12,981.06 : x
2. Step 2: Convert to fraction form
   22,540.78/31,108.46 = 12,981.06/x
3. Step 3: Cross multiply
   22,540.78x = 31,108.46 × 12,981.06
4. Step 4: Simplify right side
   22,540.78x = 403,820,720.86
5. Step 5: Solve for x
   x = 403,820,720.86/22,540.78
6. Step 6: Final answer
   x = 17,915.12