Finding the Fourth Proportional to 2,072.53, 3,108.39 and 685.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.53 : 3,108.39 = 685.61 : x
2. Step 2: Convert to fraction form
   2,072.53/3,108.39 = 685.61/x
3. Step 3: Cross multiply
   2,072.53x = 3,108.39 × 685.61
4. Step 4: Simplify right side
   2,072.53x = 2,131,143.27
5. Step 5: Solve for x
   x = 2,131,143.27/2,072.53
6. Step 6: Final answer
   x = 1,028.28