Finding the Fourth Proportional to 1,078.58, 1,488.02 and 636.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.58 : 1,488.02 = 636.32 : x
2. Step 2: Convert to fraction form
   1,078.58/1,488.02 = 636.32/x
3. Step 3: Cross multiply
   1,078.58x = 1,488.02 × 636.32
4. Step 4: Simplify right side
   1,078.58x = 946,856.89
5. Step 5: Solve for x
   x = 946,856.89/1,078.58
6. Step 6: Final answer
   x = 877.87