Finding the Fourth Proportional to 21,989.82, 30,345.24 and 12,558.39

Step by Step Solution

1. Step 1: Write the proportion equation
   21,989.82 : 30,345.24 = 12,558.39 : x
2. Step 2: Convert to fraction form
   21,989.82/30,345.24 = 12,558.39/x
3. Step 3: Cross multiply
   21,989.82x = 30,345.24 × 12,558.39
4. Step 4: Simplify right side
   21,989.82x = 381,087,358.56
5. Step 5: Solve for x
   x = 381,087,358.56/21,989.82
6. Step 6: Final answer
   x = 17,330.17