Finding the Fourth Proportional to 9,132.80, 12,603.20 and 5,406.72

Step by Step Solution

1. Step 1: Write the proportion equation
   9,132.80 : 12,603.20 = 5,406.72 : x
2. Step 2: Convert to fraction form
   9,132.80/12,603.20 = 5,406.72/x
3. Step 3: Cross multiply
   9,132.80x = 12,603.20 × 5,406.72
4. Step 4: Simplify right side
   9,132.80x = 68,141,973.50
5. Step 5: Solve for x
   x = 68,141,973.50/9,132.80
6. Step 6: Final answer
   x = 7,461.24