Finding the Fourth Proportional to 9,414.80, 12,966.12 and 9,210.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,414.80 : 12,966.12 = 9,210.72 : x
2. Step 2: Convert to fraction form
   9,414.80/12,966.12 = 9,210.72/x
3. Step 3: Cross multiply
   9,414.80x = 12,966.12 × 9,210.72
4. Step 4: Simplify right side
   9,414.80x = 119,427,300.81
5. Step 5: Solve for x
   x = 119,427,300.81/9,414.80
6. Step 6: Final answer
   x = 12,685.06