Finding the Fourth Proportional to 1,085.09, 1,497.54 and 665.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.09 : 1,497.54 = 665.72 : x
2. Step 2: Convert to fraction form
   1,085.09/1,497.54 = 665.72/x
3. Step 3: Cross multiply
   1,085.09x = 1,497.54 × 665.72
4. Step 4: Simplify right side
   1,085.09x = 996,942.33
5. Step 5: Solve for x
   x = 996,942.33/1,085.09
6. Step 6: Final answer
   x = 918.76