Finding the Fourth Proportional to 1,418.45, 2,128.98 and 725.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,418.45 : 2,128.98 = 725.61 : x
2. Step 2: Convert to fraction form
   1,418.45/2,128.98 = 725.61/x
3. Step 3: Cross multiply
   1,418.45x = 2,128.98 × 725.61
4. Step 4: Simplify right side
   1,418.45x = 1,544,807.91
5. Step 5: Solve for x
   x = 1,544,807.91/1,418.45
6. Step 6: Final answer
   x = 1,089.09