Finding the Fourth Proportional to 20,622.43, 28,459.59 and 12,123

Step by Step Solution

1. Step 1: Write the proportion equation
   20,622.43 : 28,459.59 = 12,123 : x
2. Step 2: Convert to fraction form
   20,622.43/28,459.59 = 12,123/x
3. Step 3: Cross multiply
   20,622.43x = 28,459.59 × 12,123
4. Step 4: Simplify right side
   20,622.43x = 345,015,564.11
5. Step 5: Solve for x
   x = 345,015,564.11/20,622.43
6. Step 6: Final answer
   x = 16,730.11