Finding the Fourth Proportional to 3,863.46, 5,791.61 and 2,105.86

Step by Step Solution

1. Step 1: Write the proportion equation
   3,863.46 : 5,791.61 = 2,105.86 : x
2. Step 2: Convert to fraction form
   3,863.46/5,791.61 = 2,105.86/x
3. Step 3: Cross multiply
   3,863.46x = 5,791.61 × 2,105.86
4. Step 4: Simplify right side
   3,863.46x = 12,196,319.83
5. Step 5: Solve for x
   x = 12,196,319.83/3,863.46
6. Step 6: Final answer
   x = 3,156.84