Finding the Fourth Proportional to 1,017.30, 1,403.98 and 618.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,017.30 : 1,403.98 = 618.99 : x
2. Step 2: Convert to fraction form
   1,017.30/1,403.98 = 618.99/x
3. Step 3: Cross multiply
   1,017.30x = 1,403.98 × 618.99
4. Step 4: Simplify right side
   1,017.30x = 869,051.83
5. Step 5: Solve for x
   x = 869,051.83/1,017.30
6. Step 6: Final answer
   x = 854.27