Finding the Fourth Proportional to 12,682.72, 19,025.90 and 3,918.40

Step by Step Solution

1. Step 1: Write the proportion equation
   12,682.72 : 19,025.90 = 3,918.40 : x
2. Step 2: Convert to fraction form
   12,682.72/19,025.90 = 3,918.40/x
3. Step 3: Cross multiply
   12,682.72x = 19,025.90 × 3,918.40
4. Step 4: Simplify right side
   12,682.72x = 74,551,086.56
5. Step 5: Solve for x
   x = 74,551,086.56/12,682.72
6. Step 6: Final answer
   x = 5,878.16