Finding the Fourth Proportional to 3,942.56, 5,909.86 and 2,556.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,942.56 : 5,909.86 = 2,556.78 : x
2. Step 2: Convert to fraction form
   3,942.56/5,909.86 = 2,556.78/x
3. Step 3: Cross multiply
   3,942.56x = 5,909.86 × 2,556.78
4. Step 4: Simplify right side
   3,942.56x = 15,110,211.85
5. Step 5: Solve for x
   x = 15,110,211.85/3,942.56
6. Step 6: Final answer
   x = 3,832.59