Finding the Fourth Proportional to 12,419.89, 17,139.89 and 7,115.73

Step by Step Solution

1. Step 1: Write the proportion equation
   12,419.89 : 17,139.89 = 7,115.73 : x
2. Step 2: Convert to fraction form
   12,419.89/17,139.89 = 7,115.73/x
3. Step 3: Cross multiply
   12,419.89x = 17,139.89 × 7,115.73
4. Step 4: Simplify right side
   12,419.89x = 121,962,793.89
5. Step 5: Solve for x
   x = 121,962,793.89/12,419.89
6. Step 6: Final answer
   x = 9,819.96