Finding the Fourth Proportional to 8,638.47, 12,957.15 and 3,091.52

Step by Step Solution

1. Step 1: Write the proportion equation
   8,638.47 : 12,957.15 = 3,091.52 : x
2. Step 2: Convert to fraction form
   8,638.47/12,957.15 = 3,091.52/x
3. Step 3: Cross multiply
   8,638.47x = 12,957.15 × 3,091.52
4. Step 4: Simplify right side
   8,638.47x = 40,057,288.37
5. Step 5: Solve for x
   x = 40,057,288.37/8,638.47
6. Step 6: Final answer
   x = 4,637.08