Finding the Fourth Proportional to 1,078.89, 1,488.42 and 658.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.89 : 1,488.42 = 658.90 : x
2. Step 2: Convert to fraction form
   1,078.89/1,488.42 = 658.90/x
3. Step 3: Cross multiply
   1,078.89x = 1,488.42 × 658.90
4. Step 4: Simplify right side
   1,078.89x = 980,719.94
5. Step 5: Solve for x
   x = 980,719.94/1,078.89
6. Step 6: Final answer
   x = 909.01