Finding the Fourth Proportional to 2,146.55, 3,220.05 and 685.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,146.55 : 3,220.05 = 685.37 : x
2. Step 2: Convert to fraction form
   2,146.55/3,220.05 = 685.37/x
3. Step 3: Cross multiply
   2,146.55x = 3,220.05 × 685.37
4. Step 4: Simplify right side
   2,146.55x = 2,206,909.57
5. Step 5: Solve for x
   x = 2,206,909.57/2,146.55
6. Step 6: Final answer
   x = 1,028.12