Finding the Fourth Proportional to 12,880.33, 17,776.33 and 7,216.61

Step by Step Solution

1. Step 1: Write the proportion equation
   12,880.33 : 17,776.33 = 7,216.61 : x
2. Step 2: Convert to fraction form
   12,880.33/17,776.33 = 7,216.61/x
3. Step 3: Cross multiply
   12,880.33x = 17,776.33 × 7,216.61
4. Step 4: Simplify right side
   12,880.33x = 128,284,733.92
5. Step 5: Solve for x
   x = 128,284,733.92/12,880.33
6. Step 6: Final answer
   x = 9,959.74