Finding the Fourth Proportional to 3,909.42, 5,862.72 and 1,311.76

Step by Step Solution

1. Step 1: Write the proportion equation
   3,909.42 : 5,862.72 = 1,311.76 : x
2. Step 2: Convert to fraction form
   3,909.42/5,862.72 = 1,311.76/x
3. Step 3: Cross multiply
   3,909.42x = 5,862.72 × 1,311.76
4. Step 4: Simplify right side
   3,909.42x = 7,690,481.59
5. Step 5: Solve for x
   x = 7,690,481.59/3,909.42
6. Step 6: Final answer
   x = 1,967.17