Finding the Fourth Proportional to 12,868.79, 17,753.31 and 9,091.35

Step by Step Solution

1. Step 1: Write the proportion equation
   12,868.79 : 17,753.31 = 9,091.35 : x
2. Step 2: Convert to fraction form
   12,868.79/17,753.31 = 9,091.35/x
3. Step 3: Cross multiply
   12,868.79x = 17,753.31 × 9,091.35
4. Step 4: Simplify right side
   12,868.79x = 161,401,554.87
5. Step 5: Solve for x
   x = 161,401,554.87/12,868.79
6. Step 6: Final answer
   x = 12,542.10