Finding the Fourth Proportional to 1,168.92, 1,613.18 and 644.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.92 : 1,613.18 = 644.96 : x
2. Step 2: Convert to fraction form
   1,168.92/1,613.18 = 644.96/x
3. Step 3: Cross multiply
   1,168.92x = 1,613.18 × 644.96
4. Step 4: Simplify right side
   1,168.92x = 1,040,442.22
5. Step 5: Solve for x
   x = 1,040,442.22/1,168.92
6. Step 6: Final answer
   x = 890.09