Finding the Fourth Proportional to 1,335.98, 2,003.94 and 411.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,335.98 : 2,003.94 = 411.55 : x
2. Step 2: Convert to fraction form
   1,335.98/2,003.94 = 411.55/x
3. Step 3: Cross multiply
   1,335.98x = 2,003.94 × 411.55
4. Step 4: Simplify right side
   1,335.98x = 824,716.50
5. Step 5: Solve for x
   x = 824,716.50/1,335.98
6. Step 6: Final answer
   x = 617.31