Finding the Fourth Proportional to 1,016.89, 1,403.33 and 618.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,016.89 : 1,403.33 = 618.41 : x
2. Step 2: Convert to fraction form
   1,016.89/1,403.33 = 618.41/x
3. Step 3: Cross multiply
   1,016.89x = 1,403.33 × 618.41
4. Step 4: Simplify right side
   1,016.89x = 867,833.31
5. Step 5: Solve for x
   x = 867,833.31/1,016.89
6. Step 6: Final answer
   x = 853.42