Finding the Fourth Proportional to 1,086.33, 1,498.75 and 644.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.33 : 1,498.75 = 644.14 : x
2. Step 2: Convert to fraction form
   1,086.33/1,498.75 = 644.14/x
3. Step 3: Cross multiply
   1,086.33x = 1,498.75 × 644.14
4. Step 4: Simplify right side
   1,086.33x = 965,404.83
5. Step 5: Solve for x
   x = 965,404.83/1,086.33
6. Step 6: Final answer
   x = 888.68