Finding the Fourth Proportional to 21,440.82, 29,589.87 and 12,945

Step by Step Solution

1. Step 1: Write the proportion equation
   21,440.82 : 29,589.87 = 12,945 : x
2. Step 2: Convert to fraction form
   21,440.82/29,589.87 = 12,945/x
3. Step 3: Cross multiply
   21,440.82x = 29,589.87 × 12,945
4. Step 4: Simplify right side
   21,440.82x = 383,040,867.15
5. Step 5: Solve for x
   x = 383,040,867.15/21,440.82
6. Step 6: Final answer
   x = 17,865.03