Finding the Fourth Proportional to 21,489.12, 29,652.72 and 12,058.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,489.12 : 29,652.72 = 12,058.72 : x
2. Step 2: Convert to fraction form
   21,489.12/29,652.72 = 12,058.72/x
3. Step 3: Cross multiply
   21,489.12x = 29,652.72 × 12,058.72
4. Step 4: Simplify right side
   21,489.12x = 357,573,847.72
5. Step 5: Solve for x
   x = 357,573,847.72/21,489.12
6. Step 6: Final answer
   x = 16,639.76