Finding the Fourth Proportional to 2,287.31, 3,431.05 and 644.00

Step by Step Solution

1. Step 1: Write the proportion equation
   2,287.31 : 3,431.05 = 644.00 : x
2. Step 2: Convert to fraction form
   2,287.31/3,431.05 = 644.00/x
3. Step 3: Cross multiply
   2,287.31x = 3,431.05 × 644.00
4. Step 4: Simplify right side
   2,287.31x = 2,209,577.43
5. Step 5: Solve for x
   x = 2,209,577.43/2,287.31
6. Step 6: Final answer
   x = 966.02