Finding the Fourth Proportional to 1,223.91, 1,689.12 and 726.44

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.91 : 1,689.12 = 726.44 : x
2. Step 2: Convert to fraction form
   1,223.91/1,689.12 = 726.44/x
3. Step 3: Cross multiply
   1,223.91x = 1,689.12 × 726.44
4. Step 4: Simplify right side
   1,223.91x = 1,227,035.89
5. Step 5: Solve for x
   x = 1,227,035.89/1,223.91
6. Step 6: Final answer
   x = 1,002.55