Finding the Fourth Proportional to 2,557.56, 3,835.53 and 825.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.56 : 3,835.53 = 825.78 : x
2. Step 2: Convert to fraction form
   2,557.56/3,835.53 = 825.78/x
3. Step 3: Cross multiply
   2,557.56x = 3,835.53 × 825.78
4. Step 4: Simplify right side
   2,557.56x = 3,167,303.96
5. Step 5: Solve for x
   x = 3,167,303.96/2,557.56
6. Step 6: Final answer
   x = 1,238.41