Finding the Fourth Proportional to 9,271.20, 12,789.98 and 8,210.05

Step by Step Solution

1. Step 1: Write the proportion equation
   9,271.20 : 12,789.98 = 8,210.05 : x
2. Step 2: Convert to fraction form
   9,271.20/12,789.98 = 8,210.05/x
3. Step 3: Cross multiply
   9,271.20x = 12,789.98 × 8,210.05
4. Step 4: Simplify right side
   9,271.20x = 105,006,302.27
5. Step 5: Solve for x
   x = 105,006,302.27/9,271.20
6. Step 6: Final answer
   x = 11,326.07