Finding the Fourth Proportional to 2,009.85, 3,013.79 and 839.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,009.85 : 3,013.79 = 839.50 : x
2. Step 2: Convert to fraction form
   2,009.85/3,013.79 = 839.50/x
3. Step 3: Cross multiply
   2,009.85x = 3,013.79 × 839.50
4. Step 4: Simplify right side
   2,009.85x = 2,530,072.51
5. Step 5: Solve for x
   x = 2,530,072.51/2,009.85
6. Step 6: Final answer
   x = 1,258.84