Finding the Fourth Proportional to 1,224.27, 1,689.50 and 664.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,224.27 : 1,689.50 = 664.73 : x
2. Step 2: Convert to fraction form
   1,224.27/1,689.50 = 664.73/x
3. Step 3: Cross multiply
   1,224.27x = 1,689.50 × 664.73
4. Step 4: Simplify right side
   1,224.27x = 1,123,060.96
5. Step 5: Solve for x
   x = 1,123,060.96/1,224.27
6. Step 6: Final answer
   x = 917.33