Finding the Fourth Proportional to 14,399.42, 19,860.47 and 12,786.28

Step by Step Solution

1. Step 1: Write the proportion equation
   14,399.42 : 19,860.47 = 12,786.28 : x
2. Step 2: Convert to fraction form
   14,399.42/19,860.47 = 12,786.28/x
3. Step 3: Cross multiply
   14,399.42x = 19,860.47 × 12,786.28
4. Step 4: Simplify right side
   14,399.42x = 253,941,484.61
5. Step 5: Solve for x
   x = 253,941,484.61/14,399.42
6. Step 6: Final answer
   x = 17,635.53