Finding the Fourth Proportional to 19,729.10, 27,228.72 and 13,028.78

Step by Step Solution

1. Step 1: Write the proportion equation
   19,729.10 : 27,228.72 = 13,028.78 : x
2. Step 2: Convert to fraction form
   19,729.10/27,228.72 = 13,028.78/x
3. Step 3: Cross multiply
   19,729.10x = 27,228.72 × 13,028.78
4. Step 4: Simplify right side
   19,729.10x = 354,757,002.56
5. Step 5: Solve for x
   x = 354,757,002.56/19,729.10
6. Step 6: Final answer
   x = 17,981.41