Finding the Fourth Proportional to 8,415.35, 12,630.86 and 4,258.31

Step by Step Solution

1. Step 1: Write the proportion equation
   8,415.35 : 12,630.86 = 4,258.31 : x
2. Step 2: Convert to fraction form
   8,415.35/12,630.86 = 4,258.31/x
3. Step 3: Cross multiply
   8,415.35x = 12,630.86 × 4,258.31
4. Step 4: Simplify right side
   8,415.35x = 53,786,127.73
5. Step 5: Solve for x
   x = 53,786,127.73/8,415.35
6. Step 6: Final answer
   x = 6,391.43