Finding the Fourth Proportional to 2,559.96, 3,839.90 and 828.59

Step by Step Solution

1. Step 1: Write the proportion equation
   2,559.96 : 3,839.90 = 828.59 : x
2. Step 2: Convert to fraction form
   2,559.96/3,839.90 = 828.59/x
3. Step 3: Cross multiply
   2,559.96x = 3,839.90 × 828.59
4. Step 4: Simplify right side
   2,559.96x = 3,181,679.40
5. Step 5: Solve for x
   x = 3,181,679.40/2,559.96
6. Step 6: Final answer
   x = 1,242.86