Finding the Fourth Proportional to 2,103.82, 3,156 and 805.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,103.82 : 3,156 = 805.12 : x
2. Step 2: Convert to fraction form
   2,103.82/3,156 = 805.12/x
3. Step 3: Cross multiply
   2,103.82x = 3,156 × 805.12
4. Step 4: Simplify right side
   2,103.82x = 2,540,958.72
5. Step 5: Solve for x
   x = 2,540,958.72/2,103.82
6. Step 6: Final answer
   x = 1,207.78