Finding the Fourth Proportional to 12,455.56, 18,680.15 and 3,688.42

Step by Step Solution

1. Step 1: Write the proportion equation
   12,455.56 : 18,680.15 = 3,688.42 : x
2. Step 2: Convert to fraction form
   12,455.56/18,680.15 = 3,688.42/x
3. Step 3: Cross multiply
   12,455.56x = 18,680.15 × 3,688.42
4. Step 4: Simplify right side
   12,455.56x = 68,900,220.42
5. Step 5: Solve for x
   x = 68,900,220.42/12,455.56
6. Step 6: Final answer
   x = 5,531.68