Finding the Fourth Proportional to 1,033.59, 1,425.74 and 640.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,033.59 : 1,425.74 = 640.83 : x
2. Step 2: Convert to fraction form
   1,033.59/1,425.74 = 640.83/x
3. Step 3: Cross multiply
   1,033.59x = 1,425.74 × 640.83
4. Step 4: Simplify right side
   1,033.59x = 913,653.76
5. Step 5: Solve for x
   x = 913,653.76/1,033.59
6. Step 6: Final answer
   x = 883.96