Finding the Fourth Proportional to 17,710.38, 26,529.12 and 12,789.90

Step by Step Solution

1. Step 1: Write the proportion equation
   17,710.38 : 26,529.12 = 12,789.90 : x
2. Step 2: Convert to fraction form
   17,710.38/26,529.12 = 12,789.90/x
3. Step 3: Cross multiply
   17,710.38x = 26,529.12 × 12,789.90
4. Step 4: Simplify right side
   17,710.38x = 339,304,791.89
5. Step 5: Solve for x
   x = 339,304,791.89/17,710.38
6. Step 6: Final answer
   x = 19,158.53