Finding the Fourth Proportional to 1,209.43, 1,669.04 and 685.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.43 : 1,669.04 = 685.46 : x
2. Step 2: Convert to fraction form
   1,209.43/1,669.04 = 685.46/x
3. Step 3: Cross multiply
   1,209.43x = 1,669.04 × 685.46
4. Step 4: Simplify right side
   1,209.43x = 1,144,053.53
5. Step 5: Solve for x
   x = 1,144,053.53/1,209.43
6. Step 6: Final answer
   x = 945.95