Finding the Fourth Proportional to 2,011.50, 3,018.47 and 857.25

Step by Step Solution

1. Step 1: Write the proportion equation
   2,011.50 : 3,018.47 = 857.25 : x
2. Step 2: Convert to fraction form
   2,011.50/3,018.47 = 857.25/x
3. Step 3: Cross multiply
   2,011.50x = 3,018.47 × 857.25
4. Step 4: Simplify right side
   2,011.50x = 2,587,579.12
5. Step 5: Solve for x
   x = 2,587,579.12/2,011.50
6. Step 6: Final answer
   x = 1,286.39