Finding the Fourth Proportional to 12,422.76, 17,139.20 and 8,436.92

Step by Step Solution

1. Step 1: Write the proportion equation
   12,422.76 : 17,139.20 = 8,436.92 : x
2. Step 2: Convert to fraction form
   12,422.76/17,139.20 = 8,436.92/x
3. Step 3: Cross multiply
   12,422.76x = 17,139.20 × 8,436.92
4. Step 4: Simplify right side
   12,422.76x = 144,602,059.26
5. Step 5: Solve for x
   x = 144,602,059.26/12,422.76
6. Step 6: Final answer
   x = 11,640.09