Finding the Fourth Proportional to 8,641.38, 12,956.15 and 3,091.87

Step by Step Solution

1. Step 1: Write the proportion equation
   8,641.38 : 12,956.15 = 3,091.87 : x
2. Step 2: Convert to fraction form
   8,641.38/12,956.15 = 3,091.87/x
3. Step 3: Cross multiply
   8,641.38x = 12,956.15 × 3,091.87
4. Step 4: Simplify right side
   8,641.38x = 40,058,755.43
5. Step 5: Solve for x
   x = 40,058,755.43/8,641.38
6. Step 6: Final answer
   x = 4,635.69