Finding the Fourth Proportional to 1,209.07, 1,668.67 and 685.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.07 : 1,668.67 = 685.10 : x
2. Step 2: Convert to fraction form
   1,209.07/1,668.67 = 685.10/x
3. Step 3: Cross multiply
   1,209.07x = 1,668.67 × 685.10
4. Step 4: Simplify right side
   1,209.07x = 1,143,205.82
5. Step 5: Solve for x
   x = 1,143,205.82/1,209.07
6. Step 6: Final answer
   x = 945.52