Finding the Fourth Proportional to 12,399.72, 18,684.83 and 10,256.46

Step by Step Solution

1. Step 1: Write the proportion equation
   12,399.72 : 18,684.83 = 10,256.46 : x
2. Step 2: Convert to fraction form
   12,399.72/18,684.83 = 10,256.46/x
3. Step 3: Cross multiply
   12,399.72x = 18,684.83 × 10,256.46
4. Step 4: Simplify right side
   12,399.72x = 191,640,160.22
5. Step 5: Solve for x
   x = 191,640,160.22/12,399.72
6. Step 6: Final answer
   x = 15,455.20