Finding the Fourth Proportional to 12,800.64, 17,664.72 and 7,211.52

Step by Step Solution

1. Step 1: Write the proportion equation
   12,800.64 : 17,664.72 = 7,211.52 : x
2. Step 2: Convert to fraction form
   12,800.64/17,664.72 = 7,211.52/x
3. Step 3: Cross multiply
   12,800.64x = 17,664.72 × 7,211.52
4. Step 4: Simplify right side
   12,800.64x = 127,389,481.57
5. Step 5: Solve for x
   x = 127,389,481.57/12,800.64
6. Step 6: Final answer
   x = 9,951.81