Finding the Fourth Proportional to 1,013.72, 1,398.92 and 571.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.72 : 1,398.92 = 571.56 : x
2. Step 2: Convert to fraction form
   1,013.72/1,398.92 = 571.56/x
3. Step 3: Cross multiply
   1,013.72x = 1,398.92 × 571.56
4. Step 4: Simplify right side
   1,013.72x = 799,566.72
5. Step 5: Solve for x
   x = 799,566.72/1,013.72
6. Step 6: Final answer
   x = 788.75