Finding the Fourth Proportional to 2,285.79, 3,154.35 and 1,291.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,285.79 : 3,154.35 = 1,291.20 : x
2. Step 2: Convert to fraction form
   2,285.79/3,154.35 = 1,291.20/x
3. Step 3: Cross multiply
   2,285.79x = 3,154.35 × 1,291.20
4. Step 4: Simplify right side
   2,285.79x = 4,072,896.72
5. Step 5: Solve for x
   x = 4,072,896.72/2,285.79
6. Step 6: Final answer
   x = 1,781.83