Finding the Fourth Proportional to 21,638.72, 29,861.52 and 11,702.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,638.72 : 29,861.52 = 11,702.72 : x
2. Step 2: Convert to fraction form
   21,638.72/29,861.52 = 11,702.72/x
3. Step 3: Cross multiply
   21,638.72x = 29,861.52 × 11,702.72
4. Step 4: Simplify right side
   21,638.72x = 349,461,007.33
5. Step 5: Solve for x
   x = 349,461,007.33/21,638.72
6. Step 6: Final answer
   x = 16,149.80