Finding the Fourth Proportional to 22,760.40, 31,409.52 and 12,689.48

Step by Step Solution

1. Step 1: Write the proportion equation
   22,760.40 : 31,409.52 = 12,689.48 : x
2. Step 2: Convert to fraction form
   22,760.40/31,409.52 = 12,689.48/x
3. Step 3: Cross multiply
   22,760.40x = 31,409.52 × 12,689.48
4. Step 4: Simplify right side
   22,760.40x = 398,570,475.85
5. Step 5: Solve for x
   x = 398,570,475.85/22,760.40
6. Step 6: Final answer
   x = 17,511.58