Finding the Fourth Proportional to 1,399.72, 1,932.08 and 1,007.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.72 : 1,932.08 = 1,007.89 : x
2. Step 2: Convert to fraction form
   1,399.72/1,932.08 = 1,007.89/x
3. Step 3: Cross multiply
   1,399.72x = 1,932.08 × 1,007.89
4. Step 4: Simplify right side
   1,399.72x = 1,947,324.11
5. Step 5: Solve for x
   x = 1,947,324.11/1,399.72
6. Step 6: Final answer
   x = 1,391.22