Finding the Fourth Proportional to 1,086.73, 1,499.67 and 644.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.73 : 1,499.67 = 644.84 : x
2. Step 2: Convert to fraction form
   1,086.73/1,499.67 = 644.84/x
3. Step 3: Cross multiply
   1,086.73x = 1,499.67 × 644.84
4. Step 4: Simplify right side
   1,086.73x = 967,039.70
5. Step 5: Solve for x
   x = 967,039.70/1,086.73
6. Step 6: Final answer
   x = 889.86