Finding the Fourth Proportional to 8,406.72, 12,606.42 and 2,858.57

Step by Step Solution

1. Step 1: Write the proportion equation
   8,406.72 : 12,606.42 = 2,858.57 : x
2. Step 2: Convert to fraction form
   8,406.72/12,606.42 = 2,858.57/x
3. Step 3: Cross multiply
   8,406.72x = 12,606.42 × 2,858.57
4. Step 4: Simplify right side
   8,406.72x = 36,036,334.02
5. Step 5: Solve for x
   x = 36,036,334.02/8,406.72
6. Step 6: Final answer
   x = 4,286.61