Finding the Fourth Proportional to 1,078.38, 1,488.03 and 636.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.38 : 1,488.03 = 636.23 : x
2. Step 2: Convert to fraction form
   1,078.38/1,488.03 = 636.23/x
3. Step 3: Cross multiply
   1,078.38x = 1,488.03 × 636.23
4. Step 4: Simplify right side
   1,078.38x = 946,721.89
5. Step 5: Solve for x
   x = 946,721.89/1,078.38
6. Step 6: Final answer
   x = 877.91