Finding the Fourth Proportional to 1,013.54, 1,399.37 and 664.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.54 : 1,399.37 = 664.82 : x
2. Step 2: Convert to fraction form
   1,013.54/1,399.37 = 664.82/x
3. Step 3: Cross multiply
   1,013.54x = 1,399.37 × 664.82
4. Step 4: Simplify right side
   1,013.54x = 930,329.16
5. Step 5: Solve for x
   x = 930,329.16/1,013.54
6. Step 6: Final answer
   x = 917.90