Finding the Fourth Proportional to 2,680.49, 4,020.71 and 926.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,680.49 : 4,020.71 = 926.78 : x
2. Step 2: Convert to fraction form
   2,680.49/4,020.71 = 926.78/x
3. Step 3: Cross multiply
   2,680.49x = 4,020.71 × 926.78
4. Step 4: Simplify right side
   2,680.49x = 3,726,288.88
5. Step 5: Solve for x
   x = 3,726,288.88/2,680.49
6. Step 6: Final answer
   x = 1,390.15