Finding the Fourth Proportional to 12,724.55, 17,557.59 and 7,685.39

Step by Step Solution

1. Step 1: Write the proportion equation
   12,724.55 : 17,557.59 = 7,685.39 : x
2. Step 2: Convert to fraction form
   12,724.55/17,557.59 = 7,685.39/x
3. Step 3: Cross multiply
   12,724.55x = 17,557.59 × 7,685.39
4. Step 4: Simplify right side
   12,724.55x = 134,936,838.82
5. Step 5: Solve for x
   x = 134,936,838.82/12,724.55
6. Step 6: Final answer
   x = 10,604.45