Finding the Fourth Proportional to 16,229.56, 22,415 and 12,687.72

Step by Step Solution

1. Step 1: Write the proportion equation
   16,229.56 : 22,415 = 12,687.72 : x
2. Step 2: Convert to fraction form
   16,229.56/22,415 = 12,687.72/x
3. Step 3: Cross multiply
   16,229.56x = 22,415 × 12,687.72
4. Step 4: Simplify right side
   16,229.56x = 284,395,243.80
5. Step 5: Solve for x
   x = 284,395,243.80/16,229.56
6. Step 6: Final answer
   x = 17,523.29