Finding the Fourth Proportional to 2,255.40, 3,112.49 and 1,260.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,255.40 : 3,112.49 = 1,260.72 : x
2. Step 2: Convert to fraction form
   2,255.40/3,112.49 = 1,260.72/x
3. Step 3: Cross multiply
   2,255.40x = 3,112.49 × 1,260.72
4. Step 4: Simplify right side
   2,255.40x = 3,923,981.54
5. Step 5: Solve for x
   x = 3,923,981.54/2,255.40
6. Step 6: Final answer
   x = 1,739.82