Finding the Fourth Proportional to 2,275.09, 3,139.29 and 1,280.17

Step by Step Solution

1. Step 1: Write the proportion equation
   2,275.09 : 3,139.29 = 1,280.17 : x
2. Step 2: Convert to fraction form
   2,275.09/3,139.29 = 1,280.17/x
3. Step 3: Cross multiply
   2,275.09x = 3,139.29 × 1,280.17
4. Step 4: Simplify right side
   2,275.09x = 4,018,828.80
5. Step 5: Solve for x
   x = 4,018,828.80/2,275.09
6. Step 6: Final answer
   x = 1,766.45