Finding the Fourth Proportional to 21,571.72, 29,771.72 and 12,142.08

Step by Step Solution

1. Step 1: Write the proportion equation
   21,571.72 : 29,771.72 = 12,142.08 : x
2. Step 2: Convert to fraction form
   21,571.72/29,771.72 = 12,142.08/x
3. Step 3: Cross multiply
   21,571.72x = 29,771.72 × 12,142.08
4. Step 4: Simplify right side
   21,571.72x = 361,490,605.98
5. Step 5: Solve for x
   x = 361,490,605.98/21,571.72
6. Step 6: Final answer
   x = 16,757.62