Finding the Fourth Proportional to 1,660.49, 2,488.57 and 685.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,660.49 : 2,488.57 = 685.25 : x
2. Step 2: Convert to fraction form
   1,660.49/2,488.57 = 685.25/x
3. Step 3: Cross multiply
   1,660.49x = 2,488.57 × 685.25
4. Step 4: Simplify right side
   1,660.49x = 1,705,292.59
5. Step 5: Solve for x
   x = 1,705,292.59/1,660.49
6. Step 6: Final answer
   x = 1,026.98