Finding the Fourth Proportional to 2,612.82, 3,919.82 and 857.97

Step by Step Solution

1. Step 1: Write the proportion equation
   2,612.82 : 3,919.82 = 857.97 : x
2. Step 2: Convert to fraction form
   2,612.82/3,919.82 = 857.97/x
3. Step 3: Cross multiply
   2,612.82x = 3,919.82 × 857.97
4. Step 4: Simplify right side
   2,612.82x = 3,363,084.14
5. Step 5: Solve for x
   x = 3,363,084.14/2,612.82
6. Step 6: Final answer
   x = 1,287.15