Finding the Fourth Proportional to 1,078.82, 1,488.54 and 636.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.82 : 1,488.54 = 636.62 : x
2. Step 2: Convert to fraction form
   1,078.82/1,488.54 = 636.62/x
3. Step 3: Cross multiply
   1,078.82x = 1,488.54 × 636.62
4. Step 4: Simplify right side
   1,078.82x = 947,634.33
5. Step 5: Solve for x
   x = 947,634.33/1,078.82
6. Step 6: Final answer
   x = 878.40