Finding the Fourth Proportional to 20,912.56, 31,349.59 and 9,058.88

Step by Step Solution

1. Step 1: Write the proportion equation
   20,912.56 : 31,349.59 = 9,058.88 : x
2. Step 2: Convert to fraction form
   20,912.56/31,349.59 = 9,058.88/x
3. Step 3: Cross multiply
   20,912.56x = 31,349.59 × 9,058.88
4. Step 4: Simplify right side
   20,912.56x = 283,992,229.59
5. Step 5: Solve for x
   x = 283,992,229.59/20,912.56
6. Step 6: Final answer
   x = 13,579.99