Finding the Fourth Proportional to 1,209.43, 1,668.72 and 712.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.43 : 1,668.72 = 712.09 : x
2. Step 2: Convert to fraction form
   1,209.43/1,668.72 = 712.09/x
3. Step 3: Cross multiply
   1,209.43x = 1,668.72 × 712.09
4. Step 4: Simplify right side
   1,209.43x = 1,188,278.82
5. Step 5: Solve for x
   x = 1,188,278.82/1,209.43
6. Step 6: Final answer
   x = 982.51