Finding the Fourth Proportional to 1,013.94, 1,399.25 and 571.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.94 : 1,399.25 = 571.80 : x
2. Step 2: Convert to fraction form
   1,013.94/1,399.25 = 571.80/x
3. Step 3: Cross multiply
   1,013.94x = 1,399.25 × 571.80
4. Step 4: Simplify right side
   1,013.94x = 800,091.15
5. Step 5: Solve for x
   x = 800,091.15/1,013.94
6. Step 6: Final answer
   x = 789.09