Finding the Fourth Proportional to 12,400.72, 18,686.33 and 10,257.46

Step by Step Solution

1. Step 1: Write the proportion equation
   12,400.72 : 18,686.33 = 10,257.46 : x
2. Step 2: Convert to fraction form
   12,400.72/18,686.33 = 10,257.46/x
3. Step 3: Cross multiply
   12,400.72x = 18,686.33 × 10,257.46
4. Step 4: Simplify right side
   12,400.72x = 191,674,282.52
5. Step 5: Solve for x
   x = 191,674,282.52/12,400.72
6. Step 6: Final answer
   x = 15,456.71