Finding the Fourth Proportional to 21,969.34, 30,311.34 and 12,408.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,969.34 : 30,311.34 = 12,408.72 : x
2. Step 2: Convert to fraction form
   21,969.34/30,311.34 = 12,408.72/x
3. Step 3: Cross multiply
   21,969.34x = 30,311.34 × 12,408.72
4. Step 4: Simplify right side
   21,969.34x = 376,124,930.88
5. Step 5: Solve for x
   x = 376,124,930.88/21,969.34
6. Step 6: Final answer
   x = 17,120.45