Finding the Fourth Proportional to 1,033.38, 1,426.05 and 640.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,033.38 : 1,426.05 = 640.50 : x
2. Step 2: Convert to fraction form
   1,033.38/1,426.05 = 640.50/x
3. Step 3: Cross multiply
   1,033.38x = 1,426.05 × 640.50
4. Step 4: Simplify right side
   1,033.38x = 913,385.03
5. Step 5: Solve for x
   x = 913,385.03/1,033.38
6. Step 6: Final answer
   x = 883.88