Finding the Fourth Proportional to 12,647.72, 18,966.72 and 8,740.28

Step by Step Solution

1. Step 1: Write the proportion equation
   12,647.72 : 18,966.72 = 8,740.28 : x
2. Step 2: Convert to fraction form
   12,647.72/18,966.72 = 8,740.28/x
3. Step 3: Cross multiply
   12,647.72x = 18,966.72 × 8,740.28
4. Step 4: Simplify right side
   12,647.72x = 165,774,443.48
5. Step 5: Solve for x
   x = 165,774,443.48/12,647.72
6. Step 6: Final answer
   x = 13,107.06