Finding the Fourth Proportional to 21,472.86, 29,635.17 and 12,520.35

Step by Step Solution

1. Step 1: Write the proportion equation
   21,472.86 : 29,635.17 = 12,520.35 : x
2. Step 2: Convert to fraction form
   21,472.86/29,635.17 = 12,520.35/x
3. Step 3: Cross multiply
   21,472.86x = 29,635.17 × 12,520.35
4. Step 4: Simplify right side
   21,472.86x = 371,042,700.71
5. Step 5: Solve for x
   x = 371,042,700.71/21,472.86
6. Step 6: Final answer
   x = 17,279.61