Finding the Fourth Proportional to 1,168.82, 1,612.98 and 644.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,168.82 : 1,612.98 = 644.86 : x
2. Step 2: Convert to fraction form
   1,168.82/1,612.98 = 644.86/x
3. Step 3: Cross multiply
   1,168.82x = 1,612.98 × 644.86
4. Step 4: Simplify right side
   1,168.82x = 1,040,146.28
5. Step 5: Solve for x
   x = 1,040,146.28/1,168.82
6. Step 6: Final answer
   x = 889.91