Finding the Fourth Proportional to 2,557.48, 3,835.58 and 826.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,557.48 : 3,835.58 = 826.20 : x
2. Step 2: Convert to fraction form
   2,557.48/3,835.58 = 826.20/x
3. Step 3: Cross multiply
   2,557.48x = 3,835.58 × 826.20
4. Step 4: Simplify right side
   2,557.48x = 3,168,956.20
5. Step 5: Solve for x
   x = 3,168,956.20/2,557.48
6. Step 6: Final answer
   x = 1,239.09