Finding the Fourth Proportional to 1,017.85, 1,404.23 and 664.19

Step by Step Solution

1. Step 1: Write the proportion equation
   1,017.85 : 1,404.23 = 664.19 : x
2. Step 2: Convert to fraction form
   1,017.85/1,404.23 = 664.19/x
3. Step 3: Cross multiply
   1,017.85x = 1,404.23 × 664.19
4. Step 4: Simplify right side
   1,017.85x = 932,670.16
5. Step 5: Solve for x
   x = 932,670.16/1,017.85
6. Step 6: Final answer
   x = 916.32