Finding the Fourth Proportional to 2,231.15, 3,079.37 and 1,286.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,231.15 : 3,079.37 = 1,286.78 : x
2. Step 2: Convert to fraction form
   2,231.15/3,079.37 = 1,286.78/x
3. Step 3: Cross multiply
   2,231.15x = 3,079.37 × 1,286.78
4. Step 4: Simplify right side
   2,231.15x = 3,962,471.73
5. Step 5: Solve for x
   x = 3,962,471.73/2,231.15
6. Step 6: Final answer
   x = 1,775.98