Finding the Fourth Proportional to 1,005.38, 1,508.18 and 485.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.38 : 1,508.18 = 485.98 : x
2. Step 2: Convert to fraction form
   1,005.38/1,508.18 = 485.98/x
3. Step 3: Cross multiply
   1,005.38x = 1,508.18 × 485.98
4. Step 4: Simplify right side
   1,005.38x = 732,945.32
5. Step 5: Solve for x
   x = 732,945.32/1,005.38
6. Step 6: Final answer
   x = 729.02