Finding the Fourth Proportional to 21,672.48, 29,911.68 and 12,240.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,672.48 : 29,911.68 = 12,240.72 : x
2. Step 2: Convert to fraction form
   21,672.48/29,911.68 = 12,240.72/x
3. Step 3: Cross multiply
   21,672.48x = 29,911.68 × 12,240.72
4. Step 4: Simplify right side
   21,672.48x = 366,140,499.61
5. Step 5: Solve for x
   x = 366,140,499.61/21,672.48
6. Step 6: Final answer
   x = 16,894.26