Finding the Fourth Proportional to 2,058.78, 2,843.56 and 1,640.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,058.78 : 2,843.56 = 1,640.55 : x
2. Step 2: Convert to fraction form
   2,058.78/2,843.56 = 1,640.55/x
3. Step 3: Cross multiply
   2,058.78x = 2,843.56 × 1,640.55
4. Step 4: Simplify right side
   2,058.78x = 4,665,002.36
5. Step 5: Solve for x
   x = 4,665,002.36/2,058.78
6. Step 6: Final answer
   x = 2,265.91