Finding the Fourth Proportional to 12,807.79, 17,679.61 and 9,630.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,807.79 : 17,679.61 = 9,630.31 : x
2. Step 2: Convert to fraction form
   12,807.79/17,679.61 = 9,630.31/x
3. Step 3: Cross multiply
   12,807.79x = 17,679.61 × 9,630.31
4. Step 4: Simplify right side
   12,807.79x = 170,260,153.05
5. Step 5: Solve for x
   x = 170,260,153.05/12,807.79
6. Step 6: Final answer
   x = 13,293.49