Finding the Fourth Proportional to 2,643.43, 3,961.23 and 1,081.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,643.43 : 3,961.23 = 1,081.55 : x
2. Step 2: Convert to fraction form
   2,643.43/3,961.23 = 1,081.55/x
3. Step 3: Cross multiply
   2,643.43x = 3,961.23 × 1,081.55
4. Step 4: Simplify right side
   2,643.43x = 4,284,248.50
5. Step 5: Solve for x
   x = 4,284,248.50/2,643.43
6. Step 6: Final answer
   x = 1,620.72