Finding the Fourth Proportional to 2,665.20, 4,003.92 and 1,681.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,665.20 : 4,003.92 = 1,681.05 : x
2. Step 2: Convert to fraction form
   2,665.20/4,003.92 = 1,681.05/x
3. Step 3: Cross multiply
   2,665.20x = 4,003.92 × 1,681.05
4. Step 4: Simplify right side
   2,665.20x = 6,730,789.72
5. Step 5: Solve for x
   x = 6,730,789.72/2,665.20
6. Step 6: Final answer
   x = 2,525.44