Finding the Fourth Proportional to 1,086.46, 1,498.82 and 644.11

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.46 : 1,498.82 = 644.11 : x
2. Step 2: Convert to fraction form
   1,086.46/1,498.82 = 644.11/x
3. Step 3: Cross multiply
   1,086.46x = 1,498.82 × 644.11
4. Step 4: Simplify right side
   1,086.46x = 965,397.98
5. Step 5: Solve for x
   x = 965,397.98/1,086.46
6. Step 6: Final answer
   x = 888.57