Finding the Fourth Proportional to 1,217.00, 1,679.22 and 685.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,217.00 : 1,679.22 = 685.89 : x
2. Step 2: Convert to fraction form
   1,217.00/1,679.22 = 685.89/x
3. Step 3: Cross multiply
   1,217.00x = 1,679.22 × 685.89
4. Step 4: Simplify right side
   1,217.00x = 1,151,760.21
5. Step 5: Solve for x
   x = 1,151,760.21/1,217.00
6. Step 6: Final answer
   x = 946.40