Finding the Fourth Proportional to 2,275.61, 3,140.15 and 1,280.79

Step by Step Solution

1. Step 1: Write the proportion equation
   2,275.61 : 3,140.15 = 1,280.79 : x
2. Step 2: Convert to fraction form
   2,275.61/3,140.15 = 1,280.79/x
3. Step 3: Cross multiply
   2,275.61x = 3,140.15 × 1,280.79
4. Step 4: Simplify right side
   2,275.61x = 4,021,866.31
5. Step 5: Solve for x
   x = 4,021,866.31/2,275.61
6. Step 6: Final answer
   x = 1,767.38