Finding the Fourth Proportional to 2,603.85, 3,907.31 and 961.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,603.85 : 3,907.31 = 961.55 : x
2. Step 2: Convert to fraction form
   2,603.85/3,907.31 = 961.55/x
3. Step 3: Cross multiply
   2,603.85x = 3,907.31 × 961.55
4. Step 4: Simplify right side
   2,603.85x = 3,757,049.59
5. Step 5: Solve for x
   x = 3,757,049.59/2,603.85
6. Step 6: Final answer
   x = 1,442.88