Finding the Fourth Proportional to 1,209.22, 1,668.72 and 712.17

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.22 : 1,668.72 = 712.17 : x
2. Step 2: Convert to fraction form
   1,209.22/1,668.72 = 712.17/x
3. Step 3: Cross multiply
   1,209.22x = 1,668.72 × 712.17
4. Step 4: Simplify right side
   1,209.22x = 1,188,407.85
5. Step 5: Solve for x
   x = 1,188,407.85/1,209.22
6. Step 6: Final answer
   x = 982.79