Finding the Fourth Proportional to 1,007.58, 1,390.48 and 658.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.58 : 1,390.48 = 658.06 : x
2. Step 2: Convert to fraction form
   1,007.58/1,390.48 = 658.06/x
3. Step 3: Cross multiply
   1,007.58x = 1,390.48 × 658.06
4. Step 4: Simplify right side
   1,007.58x = 915,019.27
5. Step 5: Solve for x
   x = 915,019.27/1,007.58
6. Step 6: Final answer
   x = 908.14