Finding the Fourth Proportional to 2,285.55, 3,154.55 and 1,290.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,285.55 : 3,154.55 = 1,290.87 : x
2. Step 2: Convert to fraction form
   2,285.55/3,154.55 = 1,290.87/x
3. Step 3: Cross multiply
   2,285.55x = 3,154.55 × 1,290.87
4. Step 4: Simplify right side
   2,285.55x = 4,072,107.50
5. Step 5: Solve for x
   x = 4,072,107.50/2,285.55
6. Step 6: Final answer
   x = 1,781.68