Finding the Fourth Proportional to 21,158.56, 29,199.20 and 12,204.56

Step by Step Solution

1. Step 1: Write the proportion equation
   21,158.56 : 29,199.20 = 12,204.56 : x
2. Step 2: Convert to fraction form
   21,158.56/29,199.20 = 12,204.56/x
3. Step 3: Cross multiply
   21,158.56x = 29,199.20 × 12,204.56
4. Step 4: Simplify right side
   21,158.56x = 356,363,388.35
5. Step 5: Solve for x
   x = 356,363,388.35/21,158.56
6. Step 6: Final answer
   x = 16,842.52