Finding the Fourth Proportional to 1,086.82, 1,499.58 and 644.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.82 : 1,499.58 = 644.62 : x
2. Step 2: Convert to fraction form
   1,086.82/1,499.58 = 644.62/x
3. Step 3: Cross multiply
   1,086.82x = 1,499.58 × 644.62
4. Step 4: Simplify right side
   1,086.82x = 966,659.26
5. Step 5: Solve for x
   x = 966,659.26/1,086.82
6. Step 6: Final answer
   x = 889.44