Finding the Fourth Proportional to 12,800.08, 17,665.16 and 7,211.60

Step by Step Solution

1. Step 1: Write the proportion equation
   12,800.08 : 17,665.16 = 7,211.60 : x
2. Step 2: Convert to fraction form
   12,800.08/17,665.16 = 7,211.60/x
3. Step 3: Cross multiply
   12,800.08x = 17,665.16 × 7,211.60
4. Step 4: Simplify right side
   12,800.08x = 127,394,067.86
5. Step 5: Solve for x
   x = 127,394,067.86/12,800.08
6. Step 6: Final answer
   x = 9,952.60