Finding the Fourth Proportional to 1,640.10, 2,456.20 and 1,443.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,640.10 : 2,456.20 = 1,443.09 : x
2. Step 2: Convert to fraction form
   1,640.10/2,456.20 = 1,443.09/x
3. Step 3: Cross multiply
   1,640.10x = 2,456.20 × 1,443.09
4. Step 4: Simplify right side
   1,640.10x = 3,544,517.66
5. Step 5: Solve for x
   x = 3,544,517.66/1,640.10
6. Step 6: Final answer
   x = 2,161.16