Finding the Fourth Proportional to 16,661.28, 22,993.20 and 9,210.72

Step by Step Solution

1. Step 1: Write the proportion equation
   16,661.28 : 22,993.20 = 9,210.72 : x
2. Step 2: Convert to fraction form
   16,661.28/22,993.20 = 9,210.72/x
3. Step 3: Cross multiply
   16,661.28x = 22,993.20 × 9,210.72
4. Step 4: Simplify right side
   16,661.28x = 211,783,927.10
5. Step 5: Solve for x
   x = 211,783,927.10/16,661.28
6. Step 6: Final answer
   x = 12,711.14