Finding the Fourth Proportional to 2,104.78, 3,153.68 and 1,280.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,104.78 : 3,153.68 = 1,280.56 : x
2. Step 2: Convert to fraction form
   2,104.78/3,153.68 = 1,280.56/x
3. Step 3: Cross multiply
   2,104.78x = 3,153.68 × 1,280.56
4. Step 4: Simplify right side
   2,104.78x = 4,038,476.46
5. Step 5: Solve for x
   x = 4,038,476.46/2,104.78
6. Step 6: Final answer
   x = 1,918.72