Finding the Fourth Proportional to 1,007.52, 1,390.56 and 658.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.52 : 1,390.56 = 658.20 : x
2. Step 2: Convert to fraction form
   1,007.52/1,390.56 = 658.20/x
3. Step 3: Cross multiply
   1,007.52x = 1,390.56 × 658.20
4. Step 4: Simplify right side
   1,007.52x = 915,266.59
5. Step 5: Solve for x
   x = 915,266.59/1,007.52
6. Step 6: Final answer
   x = 908.44