Finding the Fourth Proportional to 2,605.16, 3,906.55 and 1,123.68

Step by Step Solution

1. Step 1: Write the proportion equation
   2,605.16 : 3,906.55 = 1,123.68 : x
2. Step 2: Convert to fraction form
   2,605.16/3,906.55 = 1,123.68/x
3. Step 3: Cross multiply
   2,605.16x = 3,906.55 × 1,123.68
4. Step 4: Simplify right side
   2,605.16x = 4,389,698.86
5. Step 5: Solve for x
   x = 4,389,698.86/2,605.16
6. Step 6: Final answer
   x = 1,685.00