Finding the Fourth Proportional to 21,517.78, 29,697.32 and 12,086.34

Step by Step Solution

1. Step 1: Write the proportion equation
   21,517.78 : 29,697.32 = 12,086.34 : x
2. Step 2: Convert to fraction form
   21,517.78/29,697.32 = 12,086.34/x
3. Step 3: Cross multiply
   21,517.78x = 29,697.32 × 12,086.34
4. Step 4: Simplify right side
   21,517.78x = 358,931,906.61
5. Step 5: Solve for x
   x = 358,931,906.61/21,517.78
6. Step 6: Final answer
   x = 16,680.71