Finding the Fourth Proportional to 2,238.78, 3,357.31 and 851.39

Step by Step Solution

1. Step 1: Write the proportion equation
   2,238.78 : 3,357.31 = 851.39 : x
2. Step 2: Convert to fraction form
   2,238.78/3,357.31 = 851.39/x
3. Step 3: Cross multiply
   2,238.78x = 3,357.31 × 851.39
4. Step 4: Simplify right side
   2,238.78x = 2,858,380.16
5. Step 5: Solve for x
   x = 2,858,380.16/2,238.78
6. Step 6: Final answer
   x = 1,276.76