Finding the Fourth Proportional to 1,003.31, 1,503.64 and 417.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,003.31 : 1,503.64 = 417.61 : x
2. Step 2: Convert to fraction form
   1,003.31/1,503.64 = 417.61/x
3. Step 3: Cross multiply
   1,003.31x = 1,503.64 × 417.61
4. Step 4: Simplify right side
   1,003.31x = 627,935.10
5. Step 5: Solve for x
   x = 627,935.10/1,003.31
6. Step 6: Final answer
   x = 625.86