Finding the Fourth Proportional to 2,086.08, 3,129.04 and 853.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.08 : 3,129.04 = 853.15 : x
2. Step 2: Convert to fraction form
   2,086.08/3,129.04 = 853.15/x
3. Step 3: Cross multiply
   2,086.08x = 3,129.04 × 853.15
4. Step 4: Simplify right side
   2,086.08x = 2,669,540.48
5. Step 5: Solve for x
   x = 2,669,540.48/2,086.08
6. Step 6: Final answer
   x = 1,279.69