Finding the Fourth Proportional to 8,631.72, 12,945.12 and 2,390.16

Step by Step Solution

1. Step 1: Write the proportion equation
   8,631.72 : 12,945.12 = 2,390.16 : x
2. Step 2: Convert to fraction form
   8,631.72/12,945.12 = 2,390.16/x
3. Step 3: Cross multiply
   8,631.72x = 12,945.12 × 2,390.16
4. Step 4: Simplify right side
   8,631.72x = 30,940,908.02
5. Step 5: Solve for x
   x = 30,940,908.02/8,631.72
6. Step 6: Final answer
   x = 3,584.56