Finding the Fourth Proportional to 8,412.28, 12,605.31 and 3,145.86

Step by Step Solution

1. Step 1: Write the proportion equation
   8,412.28 : 12,605.31 = 3,145.86 : x
2. Step 2: Convert to fraction form
   8,412.28/12,605.31 = 3,145.86/x
3. Step 3: Cross multiply
   8,412.28x = 12,605.31 × 3,145.86
4. Step 4: Simplify right side
   8,412.28x = 39,654,540.52
5. Step 5: Solve for x
   x = 39,654,540.52/8,412.28
6. Step 6: Final answer
   x = 4,713.89